Diamine-based compound and organic light-emitting device including the same

ABSTRACT

Provided are a diamine-based compound having a certain formula and an organic light-emitting device including the same.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority from and the benefit of Korean Patent Application No. 10-2018-0031122, filed on Mar. 16, 2018, which is hereby incorporated by reference for all purposes as if fully set forth herein.

BACKGROUND Field

Exemplary embodiments of the invention relate generally to a diamine-based compound. Additionally, exemplary embodiments of the invention relate to an organic light-emitting device including the diamine-based compound.

Discussion of the Background

Organic light-emitting devices (OLEDs) are self-emission devices that, as compared with conventional devices, have wide viewing angles, high contrast ratios, short response times, and excellent characteristics in terms of brightness, driving voltage, and response speed, and they produce full-color images.

The organic light-emitting device may include a first electrode disposed on a substrate, and a hole transport region, an emission layer, an electron transport region, and a second electrode, which are sequentially disposed on the first electrode. Holes provided from the first electrode may move toward the emission layer through the hole transport region, and electrons provided from the second electrode may move toward the emission layer through the electron transport region. Carriers, such as holes and electrons, recombine in the emission layer to produce excitons. Then, the excitons are transitioned from an excited state to a ground state, thereby generating light.

The above information disclosed in this Background section is only for understanding of the background of the inventive concepts, and, therefore, it may contain information that does not constitute prior art.

SUMMARY

Additional features of the inventive concepts will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the inventive concepts.

Exemplary embodiments of the invention provide a diamine-based compound and an organic light-emitting device including the same.

According to one or more exemplary embodiments, a diamine-based compound is represented by Formula 1:

In Formula 1,

-   -   ring A may be a C₅-C₆₀ carbocyclic group or a C₂-C₆₀         heterocyclic group,     -   L₁ to L₄ may each independently be selected from a substituted         or unsubstituted C₅-C₆₀ carbocyclic group and a substituted or         unsubstituted C₂-C₆₀ heterocyclic group,     -   a1 to a4 may each independently be an integer of 0 to 5,     -   when a1 is two or more, two or more L₁(s) may be identical to or         different from each other, when a2 is two or more, two or more         L₂(s) may be identical to or different from each other, when a3         is two or more, two or more L₃(s) may be identical to or         different from each other, and when a4 is two or more, two or         more L₄(s) may be identical to or different from each other,     -   when a1 is 0, *-(L₁)_(a1)-*′ may be a single bond, when a2 is 0,         *-(L₂)_(a2)-*′ may be a single bond, when a3 is 0,         *-(L₃)_(a3)-*′ may be a single bond, and when a4 is 0,         *-(L₄)_(a4)-*′ may be a single bond,     -   Ar₁ to Ar₄ and R₁ to R₃ may each independently be selected from         hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano         group, a nitro group, an amino group, an amidino group, a         hydrazino group, a hydrazono group, a substituted or         unsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted         C₂-C₆₀ alkenyl group, a substituted or unsubstituted C₂-C₆₀         alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxy         group, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, a         substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, a         substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a         substituted or unsubstituted C₂-C₁₀ heterocycloalkenyl group, a         substituted or unsubstituted C₆-C₆₀ aryl group, a substituted or         unsubstituted C₆-C₆₀ aryloxy group, a substituted or         unsubstituted C₆-C₆₀ arylthio group, a substituted or         unsubstituted C₁-C₆₀ heteroaryl group, a substituted or         unsubstituted C₁-C₆₀ hetero aryloxy group, a substituted or         unsubstituted monovalent non-aromatic condensed polycyclic         group, a substituted or unsubstituted monovalent non-aromatic         condensed heteropolycyclic group, —Si(Q₁)(Q₂)(Q₃), —B(Q₁)(Q₂),         —C(═O)(Q₁), —N(Q₁)(Q₂), —P(═O)(Q₁)(Q₂), —P(═S)(Q₁)(Q₂),         —S(═O)(Q₁)(Q₂), and —S(═O)₂(Q₁)(Q₂),     -   wherein R₃ may not be a phenyl group substituted with two         —N(Q₁)(Q₂)(s),     -   b1 to b4 may each independently be an integer of 1 to 5,     -   when b1 is two or more, two or more Ar₁(s) may be identical to         or different from each other, when b2 is two or more, two or         more Ar₂(s) may be identical to or different from each other,         when b3 is two or more, two or more Ar₃(s) may be identical to         or different from each other, and when b4 is two or more, two or         more Ar₄(s) may be identical to or different from each other,     -   c1 may be an integer of 0 to 10, and c2 may be an integer of 0         to 2,     -   when c1 is two or more, two or more R₁(s) may be identical to or         different from each other, and when c2 is two or more, two or         more R₂(s) may be identical to or different from each other,     -   wherein the diamine-based compound represented by Formula 1 may         not be a compound represented by Formula 1B,

-   -   at least one substituent of the substituted C₅-C₆₀ carbocyclic         group, the substituted C₂-C₆₀ heterocyclic group, the         substituted C₁-C₆₀ alkyl group, the substituted C₂-C₆₀ alkenyl         group, the substituted C₂-C₆₀ alkynyl group, the substituted         C₁-C₆₀ alkoxy group, the substituted C₃-C₁₀ cycloalkyl group,         the substituted C₁-C₁₀ heterocycloalkyl group, the substituted         C₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀         heterocycloalkenyl group, the substituted C₆-C₆₀ aryl group, the         substituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀         arylthio group, the substituted C₁-C₆₀ heteroaryl group, the         substituted C₁-C₆₀ hetero aryloxy group, the substituted         monovalent non-aromatic condensed polycyclic group, and the         substituted monovalent non-aromatic condensed heteropolycyclic         group may be selected from:     -   deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a         nitro group, an amino group, an amidino group, a hydrazino         group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl         group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group;     -   a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl         group, and a C₁-C₆₀ alkoxy group, each substituted with at least         one substituent selected from deuterium, —F, —Br, —I, a hydroxyl         group, a cyano group, a nitro group, an amino group, an amidino         group, a hydrazino group, a hydrazono group, a C₃-C₁₀ cycloalkyl         group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl         group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a         C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀         heteroaryl group, a monovalent non-aromatic condensed polycyclic         group, a monovalent non-aromatic condensed heteropolycyclic         group, —Si(Q_(ii))(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂), —B(Q₁₁)(Q₁₂),         —C(═O)(Q₁₁), —S(═O)₂(Q₁₁), and —P(═O)(Q₁₁)(Q₁₂);     -   a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a         C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a         C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio         group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic         condensed polycyclic group, a monovalent non-aromatic condensed         heteropolycyclic group, a biphenyl group, and a terphenyl group;     -   a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a         C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a         C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio         group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic         condensed polycyclic group, a monovalent non-aromatic condensed         heteropolycyclic group, a biphenyl group, and a terphenyl group,         each substituted with at least one substituent selected from         deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a         nitro group, an amino group, an amidino group, a hydrazino         group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl         group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀         cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀         cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀         aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a         C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed         polycyclic group, a monovalent non-aromatic condensed         heteropolycyclic group, a biphenyl group, a terphenyl group,         —Si(Q₂₁)(Q₂₂)(Q₂₃), —N(Q₂₁)(Q₂₂), —B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁),         —S(═O)₂(Q₂₁), and —P(═O)(Q₂₁)(Q₂₂); and     -   —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),         —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂),     -   Q₁ to Q₃, Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ may each         independently be selected from hydrogen, deuterium, —F, —Cl,         —Br, —I, a hydroxyl group, a cyano group, a nitro group, an         amino group, an amidino group, a hydrazino group, a hydrazono         group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀         alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,         a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a         C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀         aryl group substituted with a C₁-C₆₀ alkyl group, a C₁-C₆₀         heteroaryl group, a monovalent non-aromatic condensed polycyclic         group, a monovalent non-aromatic condensed heteropolycyclic         group, a biphenyl group, and a terphenyl group, and     -   and *′ each indicate a binding site to a neighboring atom.

According to one or more exemplary embodiments of the invention, an organic light-emitting device includes a first electrode, a second electrode facing the first electrode, and an organic layer between the first electrode and the second electrode. The organic layer includes and an emission layer and at least one of the diamine-based compound represented to Formula 1.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention, and together with the description serve to explain the inventive concepts.

FIG. 1 is a schematic view of a light-emitting device according to an exemplary embodiment.

FIG. 2 is a schematic view of a light-emitting device according to an exemplary embodiment.

FIG. 3 is a schematic view of a light-emitting device according to an exemplary embodiment.

FIG. 4 is a schematic view of a light-emitting device according to an exemplary embodiment.

DETAILED DESCRIPTION

In the following description, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of various exemplary embodiments or implementations of the invention. As used herein “embodiments” are non-limiting examples of devices or methods employing one or more of the inventive concepts disclosed herein. It is apparent, however, that various exemplary embodiments may be practiced without these specific details or with one or more equivalent arrangements. In other instances, well-known structures and devices are shown in block diagram form in order to avoid unnecessarily obscuring various exemplary embodiments. Further, various exemplary embodiments may be different, but do not have to be exclusive. For example, specific shapes, configurations, and characteristics of an exemplary embodiment may be used or implemented in another exemplary embodiment without departing from the inventive concepts.

Unless otherwise specified, the illustrated exemplary embodiments are to be understood as providing exemplary features of varying detail of some ways in which the inventive concepts may be implemented in practice. Therefore, unless otherwise specified, the features, components, modules, layers, films, panels, regions, and/or aspects, etc. (hereinafter individually or collectively referred to as “elements”), of the various embodiments may be otherwise combined, separated, interchanged, and/or rearranged without departing from the inventive concepts.

The use of cross-hatching and/or shading in the accompanying drawings is generally provided to clarify boundaries between adjacent elements. As such, neither the presence nor the absence of cross-hatching or shading conveys or indicates any preference or requirement for particular materials, material properties, dimensions, proportions, commonalities between illustrated elements, and/or any other characteristic, attribute, property, etc., of the elements, unless specified. Further, in the accompanying drawings, the size and relative sizes of elements may be exaggerated for clarity and/or descriptive purposes. When an exemplary embodiment may be implemented differently, a specific process order may be performed differently from the described order. For example, two consecutively described processes may be performed substantially at the same time or performed in an order opposite to the described order. Also, like reference numerals denote like elements.

When an element, such as a layer or region, is referred to as being “on,” “connected to,” or “coupled to” another element, it may be directly on, connected to, or coupled to the other element or intervening elements may be present. When, however, an element is referred to as being “directly on,” “directly connected to,” or “directly coupled to” another element, there are no intervening elements present. To this end, the term “connected” may refer to physical, electrical, and/or fluid connection, with or without intervening elements. For the purposes of this disclosure, “at least one of X, Y, and Z,” “at least one element selected from X, Y, and Z,” “at least one element selected from the group consisting of X, Y, and Z,” and “at least one selected from the group consisting of X, Y, and Z” may be construed as X only, Y only, Z only, or any combination of two or more of X, Y, and Z, such as, for instance, XYZ, XYY, YZ, and ZZ. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. In addition, “A is selected from X, Y, and Z” may be construed as A is X only, Y only, or Z only. Also, “A, B, and C are each independently selected from X, Y, and Z” may be construed to mean A is X only, Y only, or Z only, B is X only, Y only, or Z only, and C is X only, Y only, or Z only.

Although the terms “first,” “second,” etc. may be used herein to describe various types of elements, these elements should not be limited by these terms. These terms are used to distinguish one element from another element. Thus, a first element discussed below could be termed a second element without departing from the teachings of the disclosure.

Spatially relative terms, such as “beneath,” “below,” “under,” “lower,” “above,” “upper,” “over,” “higher,” “side” (e.g., as in “sidewall”), and the like, may be used herein for descriptive purposes, and, thereby, to describe one elements relationship to another element(s) as illustrated in the drawings. Spatially relative terms are intended to encompass different orientations of an apparatus in use, operation, and/or manufacture in addition to the orientation depicted in the drawings. For example, if the apparatus in the drawings is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the exemplary term “below” can encompass both an orientation of above and below. Furthermore, the apparatus may be otherwise oriented (e.g., rotated 90 degrees or at other orientations), and, as such, the spatially relative descriptors used herein interpreted accordingly.

The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting. As used herein, the singular forms, “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. Moreover, the terms “comprises,” “comprising,” “includes,” and/or “including,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, components, and/or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. It is also noted that, as used herein, the terms “substantially,” “about,” and other similar terms, are used as terms of approximation and not as terms of degree, and, as such, are utilized to account for inherent deviations in measured, calculated, and/or provided values that would be recognized by one of ordinary skill in the art.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure is a part. Terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and should not be interpreted in an idealized or overly formal sense, unless expressly so defined herein.

A diamine-based compound according to an exemplary embodiment is represented by Formula 1:

In Formula 1, ring A may be a C₅-C₆₀ carbocyclic group or a C₂-C₆₀ heterocyclic group.

In one exemplary embodiment, ring A may be selected from a benzene group, a naphthalene group, an anthracene group, a phenanthrene group, a triphenylene group, a pyrene group, a chrysene group, a cyclopentadiene group, a 1,2,3,4-tetrahydronaphthalene group, a thiophene group, a furan group, a pyrrole group, an indole group, an indene group, a benzosilole group, a benzothiophene group, a benzofuran group, a carbazole group, a fluorene group, a dibenzosilole group, a dibenzothiophene group, a dibenzofuran group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, a quinoline group, an isoquinoline group, a quinoxaline group, a quinazoline group, a phenanthroline group, a pyrazole group, an imidazole group, a triazole group, an oxazole group, an isoxazole group, a thiazole group, an isothiazole group, an oxadiazole group, a thiadiazole group, a benzopyrazole group, a benzimidazole group, a benzoxazole group, a benzothiazole group, a benzoxadiazole group, a benzothiadiazole group, a 5,6,7,8-tetrahydroisoquinoline group, and a 5,6,7,8-tetrahydroquinoline group.

In one or more exemplary embodiments, ring A may be selected from a benzene group and a naphthalene group.

For example, ring A may be a benzene group, but exemplary embodiments are not limited thereto.

In Formula 1, L₁ to L₄ may each independently be selected from a substituted or unsubstituted C₅-C₆₀ carbocyclic group and a substituted or unsubstituted C₂-C₆₀ heterocyclic group.

In one embodiment, L₁ to L₄ may each independently be selected from a phenylene group, a pentalenylene group, an indenylene group, a naphthylene group, an azulenylene group, a heptalenylene group, an indacenylene group, an acenaphthylene group, a fluorenylene group, an spiro-fluorenylene group, a benzofluorenylene group, a dibenzofluorenylene group, a phenalenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthenylene group, a triphenylenyl group, a pyrenylene group, a chrysenylene group, a naphthacenylene group, a picenylene group, a perylenylene group, a pentaphenylene group, a hexacenylene group, a pentacenylene group, a rubicenylene group, a coronenylene group, an ovalenylene group, a pyrrolylene group, a thiophenylene group, a furanylene group, an imidazolylene group, a pyrazolylene group, a thiazolylene group, an isothiazolylene group, an oxazolylene group, an isoxazolylene group, a pyridinylene group, a pyrazinylene group, a pyrimidinylene group, a pyridazinylene group, an isoindolylene group, an indolylene group, an indazolylene group, a purinylene group, a quinolinylene group, an isoquinolinylene group, a benzoquinolinylene group, a phthalazinylene group, a naphthyridinylene group, a quinoxalinylene group, a quinazolinylene group, a cinnolinylene group, a carbazolylene group, a phenanthridinylene group, an acridinylene group, a phenanthrolinylene group, a phenazinylene group, a benzoimidazolylene group, a benzofuranylene group, a benzothiophenylene group, an isobenzothiazolylene group, a benzoxazolylene group, an isobenzoxazolylene group, a triazolylene group, a tetrazolylene group, an oxadiazolylene group, a triazinylene group, a dibenzofuranylene group, a dibenzothiophenylene group, a benzocarbazolylene group, and a dibenzocarbazolylene group; and

-   -   a phenylene group, a pentalenylene group, an indenylene group, a         naphthylene group, an azulenylene group, a heptalenylene group,         an indacenylene group, an acenaphthylene group, a fluorenylene         group, a spiro-fluorenylene group, a benzofluorenylene group, a         dibenzofluorenylene group, a phenalenylene group, a         phenanthrenylene group, an anthracenylene group, a         fluoranthenylene group, a triphenylenylene group, a pyrenylene         group, a chrysenylene group, a naphthacenylene group, a         picenylene group, a perylenylene group, a pentaphenylene group,         a hexacenylene group, a pentacenylene group, a rubicenylene         group, a coronenylene group, an ovalenylene group, a pyrrolylene         group, a thiophenylene group, a furanylene group, an         imidazolylene group, a pyrazolylene group, a thiazolylene group,         an isothiazolylene group, an oxazolylene group, an isoxazolylene         group, a pyridinylene group, a pyrazinylene group, a         pyrimidinylene group, a pyridazinylene group, an isoindolylene         group, an indolylene group, an indazolylene group, a purinylene         group, a quinolinylene group, an isoquinolinylene group, a         benzoquinolinylene group, a phthalazinylene group, a         naphthyridinylene group, a quinoxalinylene group, a         quinazolinylene group, a cinnolinylene group, a carbazolylene         group, a phenanthridinylene group, an acridinylene group, a         phenanthrolinylene group, a phenazinylene group, a         benzimidazolylene group, a benzofuranylene group, a         benzothiophenylene group, an isobenzothiazolylene group, a         benzoxazolylene group, an isobenzoxazolylene group, a         triazolylene group, a tetrazolylene group, an oxadiazolylene         group, a triazinylene group, a dibenzofuranylene group, a         dibenzothiophenylene group, a benzocarbazolylene group, and a         dibenzocarbazolylene group, each substituted with at least one         substituent selected from deuterium, —F, —Cl, —Br, —I, a         hydroxyl group, a cyano group, a nitro group, an amino group, an         amidino group, a hydrazine group, a hydrazone group, a         carboxylic acid group or a salt thereof, a sulfonic acid group         or a salt thereof, a phosphoric acid group or a salt thereof, a         C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group,         a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group,         a cyclohexenyl group, a phenyl group, a pentalenyl group, an         indenyl group, a naphthyl group, an azulenyl group, a heptalenyl         group, an indacenyl group, an acenaphthyl group, a fluorenyl         group, a spiro-fluorenyl group, a benzofluorenyl group, a         dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl         group, an anthracenyl group, a fluoranthenyl group, a         triphenylenyl group, a pyrenyl group, a chrysenyl group, a         naphthacenyl group, a picenyl group, a perylenyl group, a         pentaphenyl group, a hexacenyl group, a pentacenyl group, a         rubicenyl group, a coronenyl group, an ovalenyl group, a         pyrrolyl group, a thiophenyl group, a furanyl group, an         imidazolyl group, a pyrazolyl group, a thiazolyl group, an         isothiazolyl group, an oxazolyl group, an isoxazolyl group, a         pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a         pyridazinyl group, an isoindolyl group, an indolyl group, an         indazolyl group, a purinyl group, a quinolinyl group, an         isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl         group, a naphthyridinyl group, a quinoxalinyl group, a         quinazolinyl group, a cinnolinyl group, a carbazolyl group, a         phenanthridinyl group, an acridinyl group, a phenanthrolinyl         group, a phenazinyl group, a benzimidazolyl group, a         benzofuranyl group, a benzothiophenyl group, an         isobenzothiazolyl group, a benzoxazolyl group, an         isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an         oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a         dibenzothiophenyl group, a benzocarbazolyl group, a         dibenzocarbazolyl group, a thiadiazolyl group, and an         imidazopyridinyl group, but exemplary embodiments are not         limited thereto.

In one or more exemplary embodiments, L₁ to L₄ may each independently be selected from Formulae 3-1 to 3-22, but exemplary embodiments are not limited thereto:

In Formulae 3-1 to 3-22,

-   -   Y₁ may be O, S, C(Z₃)(Z₄), N(Z₅), or Si(Z₆)(Z₇),     -   Z₁ to Z₇ may each independently be selected from hydrogen,         deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a         nitro group, an amidino group, a hydrazino group, a hydrazono         group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a         cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a         cyclopentenyl group, a cyclohexenyl group, a phenyl group, a         biphenyl group, a terphenyl group, a pentalenyl group, an         indenyl group, a naphthyl group, an azulenyl group, a heptalenyl         group, an indacenyl group, an acenaphthyl group, a fluorenyl         group, a spiro-bifluorenyl group, a benzofluorenyl group, a         dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl         group, an anthracenyl group, a fluoranthenyl group, a         triphenylenyl group, a pyrenyl group, a chrysenyl group, a         naphthacenyl group, a picenyl group, a perylenyl group, a         pentaphenyl group, a hexacenyl group, a pentacenyl group, a         rubicenyl group, a coronenyl group, an ovalenyl group, a         pyrrolyl group, a thiophenyl group, a furanyl group, a silolyl         group, an imidazolyl group, a pyrazolyl group, a thiazolyl         group, an isothiazolyl group, an oxazolyl group, an isoxazolyl         group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl         group, a pyridazinyl group, an indolyl group, an isoindolyl         group, an indazolyl group, a purinyl group, a quinolinyl group,         an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl         group, a naphthyridinyl group, a quinoxalinyl group, a         quinazolinyl group, a cinnolinyl group, a phenanthridinyl group,         an acridinyl group, a phenanthrolinyl group, a phenazinyl group,         a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl         group, a benzosilolyl group, an isobenzothiazolyl group, a         benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group,         a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a         dibenzofuranyl group, a dibenzothiophenyl group, a         dibenzosilolyl group, a carbazolyl group, a benzocarbazolyl         group, a dibenzocarbazolyl group, a thiadiazolyl group, an         imidazopyridinyl group, an imidazopyrimidinyl group, a         benzonaphthyridinyl group, an azafluorenyl group, an         azaspiro-bifluorenyl group, an azacarbazolyl group, an         azadibenzofuranyl group, an azadibenzothiophenyl group, an         azadibenzosilolyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂),         —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂),     -   Q₃₁ to Q₃₃ may each independently be selected from:     -   a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, a phenyl group, a         biphenyl group, a terphenyl group, a naphthyl group, a pyridinyl         group, a pyrimidinyl group, a pyrazinyl group, a quinolinyl         group, an isoquinolinyl group, a quinoxalinyl group, and a         quinazolinyl group; and     -   a phenyl group, a biphenyl group, a terphenyl group, a naphthyl         group, a pyridinyl group, a pyrimidinyl group, a pyrazinyl         group, a quinolinyl group, an isoquinolinyl group, a         quinoxalinyl group, and a quinazolinyl group, each substituted         with at least one substituent selected from a C₁-C₁₀ alkyl         group, a C₁-C₁₀ alkoxy group, and a phenyl group,     -   d2 may be an integer of 0 to 2,     -   d3 may be an integer of 0 to 3,     -   d4 may be an integer of 0 to 4,     -   d5 may be an integer of 0 to 5,     -   d6 may be an integer of 0 to 6,     -   d8 may be an integer of 0 to 8, and     -   and *′ each indicate a binding site to a neighboring atom.

In Formula 1, a1 to a4 may each independently be an integer of 0 to 5, wherein a1 indicates the number of L₁. When a1 is two or more, two or more of L₁(s) may be identical to or different from each other. a2 to a4 may each independently be understood by referring to the description of a1.

When a1 is 0, *-(L₁)_(a1)-*′ may be a single bond, when a2 is 0, *-(L₂)_(a2)-*′ may be a single bond, when a3 is 0, *-(L₃)_(a3)-*′ may be a single bond, and when a4 is 0*-(L₄)_(a4)-, *′ may be a single bond.

In an exemplary embodiment, a1 to a4 may each independently be 0 or 1, but exemplary embodiments are not limited thereto.

In Formula 1, Ar₁ to Ar₄ and R₁ to R₃ may each independently be selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazino group, a hydrazono group, a substituted or unsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstituted C₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or unsubstituted C₂-C₁₀ heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstituted C₁-C₆₀ hetero aryloxy group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —Si(Q₁)(Q₂)(Q₃), —B(Q₁)(Q₂), —C(═O)(Q₁), —N(Q₁)(Q₂), —P(═O)(Q₁)(Q₂), —P(═S)(Q₁)(Q₂), —S(═O)(Q₁)(Q₂), and —S(═O)₂(Q₁)(Q₂),

-   -   wherein R₃ may not be a phenyl group that is substituted with         two —N(Q₁)(Q₂)(s).

Here, Q₁ to Q₃ may respectively be defined the same as described above.

In an exemplary embodiment, Ar₁ to Ar₄ and R₁ to R₃ may each independently be selected from:

-   -   hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano         group, a nitro group, an amidino group, a hydrazino group, a         hydrazono group, a C₁-C₂₀ alkyl group, a C₂-C₂₀ alkenyl group, a         C₂-C₂₀ alkynyl group, and a C₁-C₂₀ alkoxy group;     -   a C₁-C₂₀ alkyl group, a C₂-C₂₀ alkenyl group, a C₂-C₂₀ alkynyl         group, and a C₂₀ alkoxy group, each substituted with at least         one substituent selected from deuterium, —F, —Cl, —Br, —I, —CD₃,         —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano         group, a nitro group, an amidino group, a hydrazino group, a         hydrazono group, a cyclopentyl group, a cyclohexyl group, a         cycloheptyl group, a cycloctyl group, an adamantanyl group, a         norbornanyl group, a norbornenyl group, a cyclopentenyl group, a         cyclohexenyl group, a cycloheptenyl group, a phenyl group, a         naphthyl group, a pyridinyl group, a pyrimidinyl group,         —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),         —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂),     -   a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a         cycloctyl group, an adamantanyl group, a norbornanyl group, a         norbornenyl group, a cyclopentenyl group, a cyclohexenyl group,         a cycloheptenyl group, a phenyl group, a naphthyl group, a         fluorenyl group, a phenanthrenyl group, an anthracenyl group, a         fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a         chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl         group, an imidazolyl group, a pyrazolyl group, a thiazolyl         group, an isothiazolyl group, an oxazolyl group, an isoxazolyl         group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl         group, a pyridazinyl group, an isoindolyl group, an indolyl         group, an indazolyl group, a purinyl group, a quinolinyl group,         an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl         group, a quinazolinyl group, a cinnolinyl group, a carbazolyl         group, a phenanthrolinyl group, a benzimidazolyl group, a         benzofuranyl group, a benzothiophenyl group, an         isobenzothiazolyl group, a benzoxazolyl group, an         isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an         oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a         dibenzothiophenyl group, a benzocarbazolyl group, a         dibenzocarbazolyl group, an imidazopyridinyl group, and an         imidazopyrimidinyl group;     -   a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a         cycloctyl group, an adamantanyl group, a norbornanyl group, a         norbornenyl group, a cyclopentenyl group, a cyclohexenyl group,         a cycloheptenyl group, a phenyl group, a naphthyl group, a         fluorenyl group, a phenanthrenyl group, an anthracenyl group, a         fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a         chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl         group, an imidazolyl group, a pyrazolyl group, a thiazolyl         group, an isothiazolyl group, an oxazolyl group, an isoxazolyl         group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl         group, a pyridazinyl group, an isoindolyl group, an indolyl         group, an indazolyl group, a purinyl group, a quinolinyl group,         an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl         group, a quinazolinyl group, a cinnolinyl group, a carbazolyl         group, a phenanthrolinyl group, a benzimidazolyl group, a         benzofuranyl group, a benzothiophenyl group, an         isobenzothiazolyl group, a benzoxazolyl group, an         isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an         oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a         dibenzothiophenyl group, a benzocarbazolyl group, a         dibenzocarbazolyl group, an imidazopyridinyl group, and an         imidazopyrimidinyl group, each substituted with at least one         substituent selected from deuterium, —F, —Cl, —Br, —I, —CD₃,         —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano         group, a nitro group, an amidino group, a hydrazino group, a         hydrazono group, a C₁-C₂₀ alkyl group, a C₂-C₂₀ alkenyl group, a         C₂-C₂₀ alkynyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl         group, a cyclohexyl group, a cycloheptyl group, a cycloctyl         group, an adamantanyl group, a norbornanyl group, a norbornenyl         group, a cyclopentenyl group, a cyclohexenyl group, a         cycloheptenyl group, a phenyl group, a naphthyl group, a         fluorenyl group, a phenanthrenyl group, an anthracenyl group, a         fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a         chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl         group, an imidazolyl group, a pyrazolyl group, a thiazolyl         group, an isothiazolyl group, an oxazolyl group, an isoxazolyl         group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl         group, a pyridazinyl group, an isoindolyl group, an indolyl         group, an indazolyl group, a purinyl group, a quinolinyl group,         an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl         group, a quinazolinyl group, a cinnolinyl group, a carbazolyl         group, a phenanthrolinyl group, a benzimidazolyl group, a         benzofuranyl group, a benzothiophenyl group, an         isobenzothiazolyl group, a benzoxazolyl group, an         isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an         oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a         dibenzothiophenyl group, a benzocarbazolyl group, a         dibenzocarbazolyl group, an imidazopyridinyl group, an         imidazopyrimidinyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂),         —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂);         and     -   —B(Q₁)(Q₂), —P(Q₁)(Q₂), and —C(═O)(Q₁), and     -   R₃ may not be a phenyl group that is substituted with two         —N(Q₁)(Q₂)(s),     -   but embodiments of the present disclosure are not limited         thereto.

Here, Q₁ to Q₃ and Q₃₁ to Q₃₃ may respectively be defined the same as described above.

In one or more exemplary embodiments, Ar₁ to Ar₄ may each independently be selected from groups represented by Formulae 5-1 to 5-42, but exemplary embodiments are not limited thereto:

In Formulae 5-1 to 5-42,

-   -   Y₃₁ may be 0, S, C(Z₃₅)(Z₃₆), N(Z₃₇), or Si(Z₃₈)(Z₃₉),     -   Z₃₁ to Z₃₉ may each independently be selected from hydrogen,         deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a         nitro group, an amino group, an amidino group, a hydrazino         group, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy         group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl         group, a cyclopentenyl group, a cyclohexenyl group, a phenyl         group, a biphenyl group, a naphthyl group, a fluorenyl group, a         spiro-bifluorenyl group, a spiro-fluorene-benzofluorenyl group,         a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl         group, a phenanthrenyl group, an anthracenyl group, a         fluoranthenyl group, a triphenylenyl group, a pyridinyl group, a         pyrazinyl group, a pyrimidinyl group, a quinolinyl group, an         isoquinolinyl group, a benzoquinolinyl group, a naphthyridinyl         group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl         group, a phenanthridinyl group, an acridinyl group, a         phenanthrolinyl group, a phenazinyl group, a triazinyl group, a         dibenzofuranyl group, and a dibenzothiophenyl group,     -   e2 may be an integer of 0 to 2, e3 may be an integer of 0 to 3,         e4 may be an integer of 0 to 4, e5 may be an integer of 0 to 5,         e6 may be an integer of 0 to 6, e7 may be an integer of 0 to 7,         and e9 may be an integer of 0 to 9, and     -   * indicates a binding site to a neighboring atom.

In one or more exemplary embodiments, Ar₁ to Ar₄ may each independently be selected from groups represented by Formulae 6-1 to 6-11, but exemplary embodiments are not limited thereto:

In one or more exemplary embodiments, R₁ and R₂ may each independently be selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazino group, a hydrazono group, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a ter-butyl group, a pentyl group, an isoamyl group, a hexyl group, a phenyl group, and a biphenyl group, but embodiments of the present disclosure are not limited thereto.

In one or more exemplary embodiments, R3 may be selected from:

-   -   hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano         group, a nitro group, an amino group, an amidino group, a         hydrazino group, a hydrazono group, a methyl group, an ethyl         group, a propyl group, an isopropyl group, an n-butyl group, an         isobutyl group, a sec-butyl group, a ter-butyl group, a pentyl         group, an isoamyl group, and a hexyl group; and     -   groups represented by Formulae 8-1 to 8-20, but exemplary         embodiments are not limited thereto:

For example, R₃ may be selected from:

-   -   a methyl group, an ethyl group, and groups represented by         Formulae 9-1 to 9-4:

In Formula 1, b1 to b4 may each independently be an integer of 1 to 5, wherein b1 indicates the number of Ar₁. When b1 is two or more, two or more of Ar₁(s) may be identical to or different from each other. b2 to b4 may each independently be understood by referring to the description of b1.

In an exemplary embodiment, b1 to b4 may each independently be 1, but exemplary embodiments are not limited thereto.

In Formula 1, c1 may be an integer of 0 to 10, and c2 may be an integer of 0 to 2, wherein c1 indicates the number of R₁. When c1 is two or more, two or more of R₁(s) may be identical to or different from each other. c2 may be understood by referring to the description of c1.

In one exemplary embodiment, c1 and c2 may each independently be 0, but exemplary embodiments are not limited thereto.

In one exemplary embodiment, the compound represented by Formula 1 may be represented by Formula 1A, but exemplary embodiments are not limited thereto:

In Formula 1A, L₁ to L₄, a1 to a4, Ar₁ to Ar₄, b1 to b4, and R₃ may respectively be defined the same as described above in connection with Formula 1.

In one exemplary embodiment, the compound represented by Formula 1 may be selected from Compounds 1 to 39, but exemplary embodiments are not limited thereto:

The diamine-based compound represented by Formula 1 may have a back bone in which two amine groups are directly connected to the second and fourth carbon positions of a carbazole. In this regard, hole mobility may be improved along with a high T₁ energy level, thereby reducing a driving voltage of a device. In addition, holes may be confined in an emission layer, resulting in improved luminescence efficiency and color purity.

Therefore, an electronic device, for example, an organic light-emitting device, including the diamine-based compound may have low driving voltage, high efficiency, high luminance, and long lifespan.

A synthesis method for the diamine-based compound represented by Formula 1 would be apparent to those of ordinary skill in the art by referring to the following examples.

At least one of the diamine-based compounds represented by Formula 1 may be used or included between a pair of electrodes of an organic light-emitting device. For example, the diamine-based compound may be included in at least one of a hole transport region, an electron transport region, and an emission layer. For example, the diamine-based compound represented by Formula 1 may be used as a material for forming a capping layer located outside a pair of electrodes of the organic light-emitting device.

Accordingly, an organic light-emitting device according to an exemplary embodiment includes: a first electrode; a second electrode that is opposite the first electrode; and an organic layer between the first electrode and the second electrode, the organic layer including an emission layer, wherein the organic layer includes at least one of the diamine-based compounds represented by Formula 1 described above.

The expression “[an organic layer] includes at least one diamine-based compound” used herein may include a case in which “[an organic layer] includes identical compounds represented by Formula 1” and a case in which “[an organic layer] includes two or more different diamine-based compounds”.

For example, the organic layer may include, as the diamine-based compound, only Compound 1. In this regard, Compound 1 may exist only in the emission layer of the organic light-emitting device. In one or more exemplary embodiments, the organic layer may include, as the diamine-based compound, Compound 1 and Compound 2. In one or more exemplary embodiments, Compound 1 and Compound 2 may both exist in an identical layer (for example, Compound 1 and Compound 2 may both exist in an emission layer), or may exist in different layers (for example, Compound 1 may exist in an emission layer and Compound 2 may exist in an electron transport layer).

In one exemplary embodiment, the first electrode of the organic light-emitting device may be an anode, the second electrode of the organic light-emitting device may be a cathode, and the organic layer may further include a hole transport region between the first electrode and the emission layer and an electron transport region between the emission layer and the second electrode. The hole transport region may include a hole injection layer, a first hole transport layer, a second hole transport layer, an emission auxiliary layer, an electron blocking layer, or any combination thereof, and the electron transport region may include a hole blocking layer, an electron transport layer, an electron injection layer, or any combination thereof.

For example, the hole transport region may have a multi-layered structure having a hole injection layer/first hole transport layer/second hole transport layer structure, wherein constituting layers are sequentially stacked from the first electrode, but exemplary embodiments of the present disclosure are not limited thereto.

For example, in one exemplary embodiment, the hole transport region may include the diamine-based compound.

In one or more exemplary embodiments, the hole transport region may include a first hole transport layer, and the first hole transport layer may include the diamine-based compound.

In one or more exemplary embodiments, the hole transport region may include a hole injection layer, a first hole transport layer, and a second hole transport layer, and the second hole transport layer may be disposed between the first hole transport layer and the emission layer. The hole injection layer and the first hole transport layer may each include the diamine-based compound, wherein the diamine-based compound included in the hole injection layer and the diamine-based compound included in the first hole transport layer may be identical to or different from each other.

For example, the diamine-based compound included in the hole injection layer and the diamine-based compound included in the first hole transport layer may be identical to each other.

For example, the second hole transport layer may further include the diamine-based compound, wherein the diamine-based compound included in the hole injection layer and the diamine-based compound included in the second hole transport layer may be identical to or different from each other, and the diamine-based compound included in the first hole transport layer and the diamine-based compound included in the second hole transport layer may be identical to or different from each other.

For example, the diamine-based compound included in the hole injection layer and the diamine-based compound included in the second hole transport layer may be different from each other, and the diamine-based compound included in the first hole transport layer and the diamine-based compound included in the second hole transport layer may be different from each other.

In one exemplary embodiment, the hole transport region may include a p-dopant, and the p-dopant may have a lowest unoccupied molecular orbital (LUMO) level of −3.5 eV or less.

For example, the p-dopant may include a quinone derivative.

The term “an organic layer” used herein refers to a single layer and/or a plurality of layers disposed between the first electrode and the second electrode of an organic light-emitting device. A material included in the “organic layer” is not limited to an organic material.

<Description of FIG. 1>

FIG. 1 is a schematic cross-sectional view of an organic light-emitting device 10 according to an embodiment. The organic light-emitting device 10 includes a first electrode 110, an organic layer 150, and a second electrode 190.

Hereinafter, the structure of an organic light-emitting device according to an exemplary embodiment and a method of manufacturing an organic light-emitting device according to an exemplary embodiment will be described in connection with FIG. 1.

<First Electrode 110>

In FIG. 1, a substrate may be additionally disposed under the first electrode 110 or above the second electrode 190. The substrate may be a glass substrate or a plastic substrate, each having excellent mechanical strength, thermal stability, transparency, surface smoothness, ease of handling, and water resistance.

The first electrode 110 may be formed by depositing or sputtering a material for forming the first electrode 110 on the substrate. When the first electrode 110 is an anode, the material for forming the first electrode 110 may be selected from materials with a high work function to facilitate hole injection.

The first electrode 110 may be a reflective electrode, a semi-reflective electrode, or a transmissive electrode. When the first electrode 110 is a transmissive electrode, a material for forming a first electrode may be selected from indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO₂), zinc oxide (ZnO), and any combinations thereof, but exemplary embodiments are not limited thereto. In one or more exemplary embodiments, when the first electrode 110 is a semi-transmissive electrode or a reflectable electrode, a material for forming a first electrode may be selected from magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), and any combinations thereof, but exemplary embodiments are not limited thereto.

The first electrode 110 may have a single-layered structure, or a multi-layered structure including two or more layers. For example, the first electrode 110 may have a three-layered structure of ITO/Ag/ITO, but the structure of the first electrode 110 is not limited thereto.

<Organic Layer 150>

The organic layer 150 is disposed on the first electrode 110. The organic layer 150 may include an emission layer.

The organic layer 150 may further include a hole transport region disposed between the first electrode 110 and the emission layer. The organic layer 150 may also include an electron transport region disposed between the emission layer and the second electrode 190.

For example, the organic layer 150 may include at least one of the diamine-based compounds.

<Hole Transport Region in the Organic Layer 150>

The hole transport region may have i) a single-layered structure including a single layer including a single material, ii) a single-layered structure including a single layer including a plurality of different materials, or iii) a multi-layered structure having a plurality of layers including a plurality of different materials.

The hole transport region may include at least one layer selected from a hole injection layer, a first hole transport layer, a second hole transport layer, an emission auxiliary layer, and an electron blocking layer.

For example, the hole transport region may have a single-layered structure including a single layer including a plurality of different materials, or a multi-layered structure having a hole injection layer/hole transport layer structure, a hole injection layer/hole transport layer/emission auxiliary layer structure, a hole injection layer/emission auxiliary layer structure, a hole transport layer/emission auxiliary layer structure, or a hole injection layer/hole transport layer/electron blocking layer structure, wherein for each structure, constituting layers are sequentially stacked from the first electrode 110 in this stated order, but the structure of the hole transport region is not limited thereto.

The hole transport region may include the diamine-based compound represented by Formula 1.

For example, the hole injection layer, the first hole transport layer, or the second hole transport layer may include the diamine-based compound represented by Formula 1.

In addition, the hole transport region may include, in addition to the diamine-based compound represented by Formula 1, at least one selected from m-MTDATA, TDATA, 2-TNATA, NPB(NPD), β-NPB, TPD, Spiro-TPD, Spiro-NPB, methylated-NPB, TAPC, HMTPD, 4,4′,4″-tris(N-carbazolyl)triphenylamine (TCTA), polyaniline/dodecylbenzenesulfonic acid (PANI/DB SA), poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS), polyaniline/camphor sulfonic acid (PANI/CSA), polyaniline/poly(4-styrenesulfonate) (PANI/PSS), a compound represented by Formula 201, and a compound represented by Formula 202:

In Formulae 201 and 202,

-   -   L₂₀₁ to L₂₀₄ may each independently be selected from a         substituted or unsubstituted C₃-C₁₀ cycloalkylene group, a         substituted or unsubstituted C₁-C₁₀ heterocycloalkylene group, a         substituted or unsubstituted C₃-C₁₀ cycloalkenylene group, a         substituted or unsubstituted C₁-C₁₀ heterocycloalkenylene group,         a substituted or unsubstituted C₆-C₆₀ arylene group, a         substituted or unsubstituted C₁-C₆₀ heteroarylene group, a         substituted or unsubstituted divalent non-aromatic condensed         polycyclic group, and a substituted or unsubstituted divalent         non-aromatic condensed heteropolycyclic group,     -   L₂₀₅ may be selected from *—O—*′, *—S—*′, *—N(Q₂₀₁)-*′, a         substituted or unsubstituted C₁-C₂₀ alkylene group, a         substituted or unsubstituted C₂-C₂₀ alkenylene group, a         substituted or unsubstituted C₃-C₁₀ cycloalkylene group, a         substituted or unsubstituted C₁-C₁₀ heterocycloalkylene group, a         substituted or unsubstituted C₃-C₁₀ cycloalkenylene group, a         substituted or unsubstituted C₁-C₁₀ heterocycloalkenylene group,         a substituted or unsubstituted C₆-C₆₀ arylene group, a         substituted or unsubstituted C₁-C₆₀ heteroarylene group, a         substituted or unsubstituted divalent non-aromatic condensed         polycyclic group, and a substituted or unsubstituted divalent         non-aromatic condensed heteropolycyclic group,     -   xa1 to xa4 may each independently be an integer of 0 to 3,     -   xa5 may be an integer of 1 to 10, and     -   R₂₀₁ to R₂₀₄ and Q₂₀₁ may each independently be selected from a         substituted or unsubstituted C₃-C₁₀ cycloalkyl group, a         substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, a         substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a         substituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, a         substituted or unsubstituted C₆-C₆₀ aryl group, a substituted or         unsubstituted C₆-C₆₀ aryloxy group, a substituted or         unsubstituted C₆-C₆₀ arylthio group, a substituted or         unsubstituted C₁-C₆₀ heteroaryl group, a substituted or         unsubstituted monovalent non-aromatic condensed polycyclic         group, and a substituted or unsubstituted monovalent         non-aromatic condensed heteropolycyclic group.

For example, in Formula 202, R₂₀₁ and R₂₀₂ may optionally be linked each other via a single bond, a dimethyl-methylene group, or a diphenyl-methylene group, and R₂₀₃ and R₂₀₄ may optionally be linked each other via a single bond, a dimethyl-methylene group, or a diphenyl-methylene group.

In one exemplary embodiment, in Formulae 201 and 202,

-   -   L₂₀₁ to L₂₀₅ may each independently be selected from:     -   a phenylene group, a pentalenylene group, an indenylene group, a         naphthylene group, an azulenylene group, a heptalenylene group,         an indacenylene group, an acenaphthylene group, a fluorenylene         group, a spiro-bifluorenylene group, a benzofluorenylene group,         a dibenzofluorenylene group, a phenalenylene group, a         phenanthrenylene group, an anthracenylene group, a         fluoranthenylene group, a triphenylenylene group, a pyrenylene         group, a chrysenylene group, a naphthacenylene group, a         picenylene group, a perylenylene group, a pentaphenylene group,         a hexacenylene group, a pentacenylene group, a rubicenylene         group, a coronenylene group, an ovalenylene group, a         thiophenylene group, a furanylene group, a carbazolylene group,         an indolylene group, an isoindolylene group, a benzofuranylene         group, a benzothiophenylene group, a dibenzofuranylene group, a         dibenzothiophenylene group, a benzocarbazolylene group, a         dibenzocarbazolylene group, a dibenzosilolylene group, and a         pyridinylene group; and     -   a phenylene group, a pentalenylene group, an indenylene group, a         naphthylene group, an azulenylene group, a heptalenylene group,         an indacenylene group, an acenaphthylene group, a fluorenylene         group, a spiro-bifluorenylene group, a benzofluorenylene group,         a dibenzofluorenylene group, a phenalenylene group, a         phenanthrenylene group, an anthracenylene group, a         fluoranthenylene group, a triphenylenylene group, a pyrenylene         group, a chrysenylene group, a naphthacenylene group, a         picenylene group, a perylenylene group, a pentaphenylene group,         a hexacenylene group, a pentacenylene group, a rubicenylene         group, a coronenylene group, an ovalenylene group, a         thiophenylene group, a furanylene group, a carbazolylene group,         an indolylene group, an isoindolylene group, a benzofuranylene         group, a benzothiophenylene group, a dibenzofuranylene group, a         dibenzothiophenylene group, a benzocarbazolylene group, a         dibenzocarbazolylene group, a dibenzosilolylene group, and a         pyridinylene group, each substituted with at least one         substituent selected from deuterium, —F, —Cl, —Br, —I, a         hydroxyl group, a cyano group, a nitro group, an amidino group,         a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a         C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexyl group, a         cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,         a phenyl group, a biphenyl group, a terphenyl group, a phenyl         group substituted with a C₁-C₁₀ alkyl group, a phenyl group         substituted with —F, a pentalenyl group, an indenyl group, a         naphthyl group, an azulenyl group, a heptalenyl group, an         indacenyl group, an acenaphthyl group, a fluorenyl group, a         spiro-bifluorenyl group, a benzofluorenyl group, a         dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl         group, an anthracenyl group, a fluoranthenyl group, a         triphenylenyl group, a pyrenyl group, a chrysenyl group, a         naphthacenyl group, a picenyl group, a perylenyl group, a         pentaphenyl group, a hexacenyl group, a pentacenyl group, a         rubicenyl group, a coronenyl group, an ovalenyl group, a         thiophenyl group, a furanyl group, a carbazolyl group, an         indolyl group, an isoindolyl group, a benzofuranyl group, a         benzothiophenyl group, a dibenzofuranyl group, a         dibenzothiophenyl group, a benzocarbazolyl group, a         dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl         group, —Si(Q₃₁)(Q₃₂)(Q₃₃), and —N(Q₃₁)(Q₃₂), and     -   Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀         alkyl group, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl         group, a terphenyl group, and a naphthyl group.

In one or more exemplary embodiments, xa1 to xa4 may each independently be 0, 1, or 2.

In one or more exemplary embodiments, xa5 may be 1, 2, 3, or 4.

In one or more exemplary embodiments, R₂₀₁ to R₂₀₄ and Q₂₀₁ may each independently be selected from:

-   -   a phenyl group, a biphenyl group, a terphenyl group, a         pentalenyl group, an indenyl group, a naphthyl group, an         azulenyl group, a heptalenyl group, an indacenyl group, an         acenaphthyl group, a fluorenyl group, a spiro-bifluorenyl group,         a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl         group, a phenanthrenyl group, an anthracenyl group, a         fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a         chrysenyl group, a naphthacenyl group, a picenyl group, a         perylenyl group, a pentaphenyl group, a hexacenyl group, a         pentacenyl group, a rubicenyl group, a coronenyl group, an         ovalenyl group, a thiophenyl group, a furanyl group, a         carbazolyl group, an indolyl group, an isoindolyl group, a         benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl         group, a dibenzothiophenyl group, a benzocarbazolyl group, a         dibenzocarbazolyl group, a dibenzosilolyl group, and a pyridinyl         group; and     -   a phenyl group, a biphenyl group, a terphenyl group, a         pentalenyl group, an indenyl group, a naphthyl group, an         azulenyl group, a heptalenyl group, an indacenyl group, an         acenaphthyl group, a fluorenyl group, a spiro-bifluorenyl group,         a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl         group, a phenanthrenyl group, an anthracenyl group, a         fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a         chrysenyl group, a naphthacenyl group, a picenyl group, a         perylenyl group, a pentaphenyl group, a hexacenyl group, a         pentacenyl group, a rubicenyl group, a coronenyl group, an         ovalenyl group, a thiophenyl group, a furanyl group, a         carbazolyl group, an indolyl group, an isoindolyl group, a         benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl         group, a dibenzothiophenyl group, a benzocarbazolyl group, a         dibenzocarbazolyl group, a dibenzosilolyl group, and a pyridinyl         group, each substituted with at least one substituent selected         from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano         group, a nitro group, an amidino group, a hydrazino group, a         hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a         cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a         cyclopentenyl group, a cyclohexenyl group, a phenyl group, a         biphenyl group, a terphenyl group, a phenyl group substituted         with a C₁-C₁₀ alkyl group, a phenyl group substituted with —F, a         pentalenyl group, an indenyl group, a naphthyl group, an         azulenyl group, a heptalenyl group, an indacenyl group, an         acenaphthyl group, a fluorenyl group, a spiro-bifluorenyl group,         a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl         group, a phenanthrenyl group, an anthracenyl group, a         fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a         chrysenyl group, a naphthacenyl group, a picenyl group, a         perylenyl group, a pentaphenyl group, a hexacenyl group, a         pentacenyl group, a rubicenyl group, a coronenyl group, an         ovalenyl group, a thiophenyl group, a furanyl group, a         carbazolyl group, an indolyl group, an isoindolyl group, a         benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl         group, a dibenzothiophenyl group, a benzocarbazolyl group, a         dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl         group, —Si(Q₃₁)(Q₃₂)(Q₃₃), and —N(Q₃₁)(Q₃₂), and     -   Q₃₁ to Q₃₃ may respectively be defined the same as described         above.

In one or more embodiments, in Formula 201, at least one selected from R₂₀₁ to R₂₀₃ may each independently be selected from:

-   -   a fluorenyl group, a spiro-bifluorenyl group, a carbazolyl         group, a dibenzofuranyl group, and a dibenzothiophenyl group;         and     -   a fluorenyl group, a spiro-bifluorenyl group, a carbazolyl         group, a dibenzofuranyl group, and a dibenzothiophenyl group,         each substituted with at least one substituent selected from         deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a         nitro group, an amidino group, a hydrazino group, a hydrazono         group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a         cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a         cyclopentenyl group, a cyclohexenyl group, a phenyl group, a         biphenyl group, a terphenyl group, a phenyl group substituted         with a C₁-C₁₀ alkyl group, a phenyl group substituted with —F, a         naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a         carbazolyl group, a dibenzofuranyl group, and a         dibenzothiophenyl group, but exemplary embodiments are not         limited thereto.

In one or more exemplary embodiments, in Formula 202, i) R₂₀₁ and R₂₀₂ may be linked via a single bond, and/or ii) R₂₀₃ and R₂₀₄ may be linked via a single bond.

In one or more exemplary embodiments, in Formula 202, at least one selected from R₂₀₁ to R₂₀₄ may be selected from:

-   -   a carbazolyl group; and     -   a carbazolyl group substituted with at least one selected from         deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a         nitro group, an amidino group, a hydrazino group, a hydrazono         group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl         group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl         group, a cyclohexenyl group, a phenyl group, a biphenyl group, a         terphenyl group, a phenyl group substituted with a C₁-C₁₀ alkyl         group, a phenyl group substituted with —F, a naphthyl group, a         fluorenyl group, a spiro-bifluorenyl group, a carbazolyl group,         a dibenzofuranyl group, and a dibenzothiophenyl group, but         exemplary embodiments are not limited thereto.

The compound represented by Formula 201 may be represented by Formula 201A:

For example, the compound represented by Formula 201 may be represented by Formula 201A(1), but exemplary embodiments are not limited thereto:

In one exemplary embodiment, the compound represented by Formula 201 may be represented by Formula 201A-1, but exemplary embodiments are not limited thereto:

In one or more exemplary embodiments, the compound represented by Formula 202 may be represented by Formula 202A:

In one or more exemplary embodiments, the compound represented by Formula 202 may be represented by Formula 202A-1:

In Formulae 201A, 201A(1), 201A-1, 202A, and 202A-1,

-   -   L₂₀₁ to L₂₀₃, xa1 to xa3, xa5, and R₂₀₂ to R₂₀₄ may respectively         be defined the same as described above,     -   R₂₁₁ and R₂₁₂ may respectively be defined the same as described         in connection with R₂₀₃,     -   R₂₁₃ to R₂₁₇ may each independently be selected from hydrogen,         deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a         nitro group, an amidino group, a hydrazino group, a hydrazono         group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a         cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a         cyclopentenyl group, a cyclohexenyl group, a phenyl group, a         biphenyl group, a terphenyl group, a phenyl group substituted         with a C₁-C₁₀ alkyl group, a phenyl group substituted with —F, a         pentalenyl group, an indenyl group, a naphthyl group, an         azulenyl group, a heptalenyl group, an indacenyl group, an         acenaphthyl group, a fluorenyl group, a spiro-bifluorenyl group,         a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl         group, a phenanthrenyl group, an anthracenyl group, a         fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a         chrysenyl group, a naphthacenyl group, a picenyl group, a         perylenyl group, a pentaphenyl group, a hexacenyl group, a         pentacenyl group, a rubicenyl group, a coronenyl group, an         ovalenyl group, a thiophenyl group, a furanyl group, a         carbazolyl group, an indolyl group, an isoindolyl group, a         benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl         group, a dibenzothiophenyl group, a benzocarbazolyl group, a         dibenzocarbazolyl group, a dibenzosilolyl group, and a pyridinyl         group.

The hole transport region may include at least one compound selected from Compounds HT1 to HT39, but exemplary embodiments are not limited thereto:

A thickness of the hole transport region may be from about 100 Å to about 10,000 Å, for example, about 100 Å to about 3,000 Å. When the hole transport region includes at least one selected from a hole injection layer and a hole transport layer, a thickness of the hole injection layer may be in a range of about 100 Å to about 9,000 Å, for example, about 100 Å to about 1,000 Å, and a thickness of the hole transport layer may be in a range of about 50 Å to about 2,000 Å, for example about 100 Å to about 1,500 Å.

For example, in one exemplary embodiment, a thickness of the first hole transport layer or the second hole transport layer may be in a range of about 200 Å to about 400 Å.

When the thicknesses of the hole transport region, the hole injection layer, and the hole transport layer are within these ranges, excellent hole transporting characteristics may be obtained without a substantial increase in driving voltage.

The emission auxiliary layer may increase light-emission efficiency by compensating for an optical resonance distance according to the wavelength of light emitted by an emission layer, and the electron blocking layer may block the flow of electrons from an electron transport region. The emission auxiliary layer and the electron blocking layer may each independently include the materials as described above.

<p-Dopant>

The hole transport region may further include, in addition to these materials, a charge-generation material for the improvement of conductive properties. The charge-generation material may be homogeneously or non-homogeneously dispersed in the hole transport region.

The charge-generation material may be, for example, a p-dopant.

In one embodiment, the p-dopant may have a LUMO level of −3.5 eV.

The p-dopant may include at least one selected from a quinone derivative, a metal oxide, and a cyano group-containing compound, but exemplary embodiments of the present disclosure are not limited thereto.

In one exemplary embodiment, the p-dopant may include at least one selected from:

a quinone derivative, such as tetracyanoquinodimethane (TCNQ) and 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ);

-   -   a metal oxide, such as tungsten oxide or molybdenum oxide;     -   1,4,5,8,9,12-hexaazatriphenylene-hexacarbonitrile (HAT-CN); and     -   a compound represented by Formula 221:     -   but exemplary embodiments of the present disclosure are not         limited thereto:

In Formula 221,

-   -   R₂₂₁ to R₂₂₃ may each independently be selected from a         substituted or unsubstituted C₃-C₁₀ cycloalkyl group, a         substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, a         substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a         substituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, a         substituted or unsubstituted C₆-C₆₀ aryl group, a substituted or         unsubstituted C₁-C₆₀ heteroaryl group, a substituted or         unsubstituted monovalent non-aromatic condensed polycyclic         group, and a substituted or unsubstituted monovalent         non-aromatic condensed heteropolycyclic group, wherein at least         one selected from R₂₂₁ to R₂₂₃ may have at least one substituent         selected from a cyano group, —F, —Cl, —Br, —I, a C₁-C₂₀ alkyl         group substituted with —F, a C₁-C₂₀ alkyl group substituted with         —Cl, a C₁-C₂₀ alkyl group substituted with —Br, and a C₁-C₂₀         alkyl group substituted with —I.

<Emission Layer in the Organic Layer 150>

When the organic light-emitting device 10 is a full-color organic light-emitting device, the emission layer may be patterned into a red emission layer, a green emission layer, or a blue emission layer, according to a sub-pixel. In one or more exemplary embodiments, the emission layer may have a stacked structure of two or more layers selected from a red emission layer, a green emission layer, and a blue emission layer, in which the two or more layers contact each other or are separated from each other. In one or more exemplary embodiments, the emission layer may include two or more materials selected from a red light-emitting material, a green light-emitting material, and a blue light-emitting material, in which the two or more materials are mixed with each other in a single layer to emit white light.

The emission layer may include a host and a dopant. The dopant may include at least one selected from a phosphorescent dopant and a fluorescent dopant.

In the emission layer, an amount of the dopant may be generally in a range of about 0.01 parts by weight to about 30 parts by weight based on 100 parts by weight of the host, but exemplary embodiments are not limited thereto.

A thickness of the emission layer may be in a range of about 100 Å to about 1,000 Å, for example, about 200 Å to about 600 Å. When the thickness of the emission layer is within this range, excellent emission characteristics may be obtained without a substantial increase in driving voltage.

<Host in the Emission Layer>

The host may include a compound represented by Formula 301:

[Ar₃₀₁]_(xb11)-[(L₃₀₁)_(xb1)-R₃₀₁]_(xb21)   <Formula 301>

In Formula 301,

-   -   Ar₃₀₁ may be a substituted or unsubstituted C₅-C₆₀ carbocyclic         group or a substituted or unsubstituted C₁-C₆₀ heterocyclic         group,     -   xb11 may be 1, 2, or 3,     -   L₃₀₁ may be selected from a substituted or unsubstituted C₃-C₁₀         cycloalkylene group, a substituted or unsubstituted C₁-C₁₀         heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀         cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀         heterocycloalkenylene group, a substituted or unsubstituted         C₆-C₆₀ arylene group, a substituted or unsubstituted C₁-C₆₀         heteroarylene group, a substituted or unsubstituted divalent         non-aromatic condensed polycyclic group, and a substituted or         unsubstituted divalent non-aromatic condensed heteropolycyclic         group,     -   xb1 may be an integer of 0 to 5,     -   R₃₀₁ may be selected from deuterium, —F, —Cl, —Br, —I, a         hydroxyl group, a cyano group, a nitro group, an amidino group,         a hydrazino group, a hydrazono group, a substituted or         unsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted         C₂-C₆₀ alkenyl group, a substituted or unsubstituted C₂-C₆₀         alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxy         group, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, a         substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, a         substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a         substituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, a         substituted or unsubstituted C₆-C₆₀ aryl group, a substituted or         unsubstituted C₆-C₆₀ aryloxy group, a substituted or         unsubstituted C₆-C₆₀ arylthio group, a substituted or         unsubstituted C₁-C₆₀ heteroaryl group, a substituted or         unsubstituted monovalent non-aromatic condensed polycyclic         group, a substituted or unsubstituted monovalent non-aromatic         condensed heteropolycyclic group, —Si(Q₃₀₁)(Q₃₀₂)(Q₃₀₃),         —N(Q₃₀₁)(Q₃₀₂), —B(Q₃₀₁)(Q₃₀₂), —C(═O)(Q₃₀₁), —S(═O)₂(Q₃₀₁), and         —P(═O)(Q₃₀₁)(Q₃₀₂),     -   xb21 may be an integer of 1 to 5,     -   Q₃₀₁ to Q₃₀₃ may each independently be selected from a C₁-C₁₀         alkyl group, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl         group, a terphenyl group, and a naphthyl group, but exemplary         embodiments are not limited thereto.

In one exemplary embodiment, in Formula 301, Ar₃₀₁ may be selected from:

-   -   a naphthalene group, a fluorene group, a spiro-bifluorene group,         a benzofluorene group, a dibenzofluorene group, a phenalene         group, a phenanthrene group, an anthracene group, a fluoranthene         group, a triphenylene group, a pyrene group, a chrysene group, a         naphthacene group, a picene group, a perylene group, a         pentaphene group, an indenoanthracene group, a dibenzofuran         group, and a dibenzothiophene group; and     -   a naphthalene group, a fluorene group, a spiro-bifluorene group,         a benzofluorene group, a dibenzofluorene group, a phenalene         group, a phenanthrene group, an anthracene group, a fluoranthene         group, a triphenylene group, a pyrene group, a chrysene group, a         naphthacene group, a picene group, a perylene group, a         pentaphene group, an indenoanthracene group, a dibenzofuran         group, and a dibenzothiophene group, each substituted with at         least one substituent selected from deuterium, —F, —Cl, —Br, —I,         a hydroxyl group, a cyano group, a nitro group, an amidino         group, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl         group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group,         a terphenyl group, a naphthyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃),         —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁) and         —P(═O)(Q₃₁)(Q₃₂), and     -   Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀         alkyl group, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl         group, a terphenyl group, and a naphthyl group, but exemplary         embodiments are not limited thereto.

In Formula 301, when xb11 is two or more, two or more of Ar₃₀₁(s) may be linked via a single bond.

In one or more exemplary embodiments, the compound represented by Formula 301 may be represented by Formula 301-1 or Formula 301-2:

In Formulae 301-1 to 301-2,

-   -   A₃₀₁ to A₃₀₄ may each independently be selected from a benzene,         a naphthalene, a phenanthrene, a fluoranthene, a triphenylene, a         pyrene, a chrysene, a pyridine, a pyrimidine, an indene, a         fluorene, a spiro-bifluorene, a benzofluorene, a         dibenzofluorene, an indole, a carbazole, benzocarbazole,         dibenzocarbazole, a furan, a benzofuran, a dibenzofuran, a         naphthofuran, a benzonaphthofuran, dinaphthofuran, a thiophene,         a benzothiophene, a dibenzothiophene, a naphthothiophene, a         benzonaphthothiophene, and a dinaphthothiophene,

X₃₀₁ may be O, S, or N-[(L₃₀₄)_(xb4)-R₃₀₄],

-   -   R₃₁₁ to R₃₁₄ may each independently be selected from hydrogen,         deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a         nitro group, an amidino group, a hydrazino group, a hydrazono         group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl         group, a biphenyl group, a terphenyl group, a naphthyl group         —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),         —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂),     -   xb22 and xb23 may each independently be 0, 1, or 2,     -   L₃₀₁, xb1, R₃₀₁, and Q₃₁ to Q₃₃ may respectively be defined the         same as described above,     -   L₃₀₂ to L₃₀₄ may respectively be defined the same as described         in connection with L₃₀₁,     -   xb2 to xb4 may respectively be defined the same as described in         connection with xb1, and     -   R₃₀₂ to R₃₀₄ may respectively be defined the same as described         in connection with R₃₀₁.

For example, in Formulae 301, 301-1, and 301-2, L₃₀₁ to L₃₀₄ may each independently be selected from:

-   -   a phenylene group, a naphthylene group, a fluorenylene group, a         spiro-bifluorenylene group, a benzofluorenylene group, a         dibenzofluorenylene group, a phenanthrenylene group, an         anthracenylene group, a fluoranthenylene group, a         triphenylenylene group, a pyrenylene group, a chrysenylene         group, a perylenylene group, a pentaphenylene group, a         hexacenylene group, a pentacenylene group, a thiophenylene         group, a furanylene group, a carbazolylene group, an indolylene         group, an isoindolylene group, a benzofuranylene group, a         benzothiophenylene group, a dibenzofuranylene group, a         dibenzothiophenylene group, a benzocarbazolylene group, a         dibenzocarbazolylene group, a dibenzosilolylene group, a         pyridinylene group, an imidazolylene group, a pyrazolylene         group, a thiazolylene group, an isothiazolylene group, an         oxazolylene group, an isoxazolylene group, a thiadiazolylene         group, an oxadiazolylene group, a pyrazinylene group, a         pyrimidinylene group, a pyridazinylene group, a triazinylene         group, a quinolinylene group, an isoquinolinylene group, a         benzoquinolinylene group, a phthalazinylene group, a         naphthyridinylene group, a quinoxalinylene group, a         quinazolinylene group, a cinnolinylene group, a         phenanthridinylene group, an acridinylene group, a         phenanthrolinylene group, a phenazinylene group, a         benzimidazolylene group, an isobenzothiazolylene group, a         benzoxazolylene group, an isobenzoxazolylene group, a         triazolylene group, a tetrazolylene group, an         imidazopyridinylene group, an imidazopyrimidinylene group, and         an azacarbazolylene group; and     -   a phenylene group, a naphthylene group, a fluorenylene group, a         spiro-bifluorenylene group, a benzofluorenylene group, a         dibenzofluorenylene group, a phenanthrenylene group, an         anthracenylene group, a fluoranthenylene group, a         triphenylenylene group, a pyrenylene group, a chrysenylene         group, a perylenylene group, a pentaphenylene group, a         hexacenylene group, a pentacenylene group, a thiophenylene         group, a furanylene group, a carbazolylene group, an indolylene         group, an isoindolylene group, a benzofuranylene group, a         benzothiophenylene group, a dibenzofuranylene group, a         dibenzothiophenylene group, a benzocarbazolylene group, a         dibenzocarbazolylene group, a dibenzosilolylene group, a         pyridinylene group, an imidazolylene group, a pyrazolylene         group, a thiazolylene group, an isothiazolylene group, an         oxazolylene group, an isoxazolylene group, a thiadiazolylene         group, an oxadiazolylene group, a pyrazinylene group, a         pyrimidinylene group, a pyridazinylene group, a triazinylene         group, a quinolinylene group, an isoquinolinylene group, a         benzoquinolinylene group, a phthalazinylene group, a         naphthyridinylene group, a quinoxalinylene group, a         quinazolinylene group, a cinnolinylene group, a         phenanthridinylene group, an acridinylene group, a         phenanthrolinylene group, a phenazinylene group, a         benzimidazolylene group, an isobenzothiazolylene group, a         benzoxazolylene group, an isobenzoxazolylene group, a         triazolylene group, a tetrazolylene group, an         imidazopyridinylene group, an imidazopyrimidinylene group, and         an azacarbazolylene group, each substituted with at least one         substituent selected from deuterium, —F, —Cl, —Br, —I, a         hydroxyl group, a cyano group, a nitro group, an amidino group,         a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a         C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a         terphenyl group, a naphthyl group, a fluorenyl group, a         spiro-bifluorenyl group, a benzofluorenyl group, a         dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl         group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl         group, a chrysenyl group, a perylenyl group, a pentaphenyl         group, a hexacenyl group, a pentacenyl group, a thiophenyl         group, a furanyl group, a carbazolyl group, an indolyl group, an         isoindolyl group, a benzofuranyl group, a benzothiophenyl group,         a dibenzofuranyl group, a dibenzothiophenyl group, a         benzocarbazolyl group, a dibenzocarbazolyl group, a         dibenzosilolyl group, a pyridinyl group, an imidazolyl group, a         pyrazolyl group, a thiazolyl group, an isothiazolyl group, an         oxazolyl group, an isoxazolyl group, a thiadiazolyl group, an         oxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a         pyridazinyl group, a triazinyl group, a quinolinyl group, an         isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl         group, a naphthyridinyl group, a quinoxalinyl group, a         quinazolinyl group, a cinnolinyl group, a phenanthridinyl group,         an acridinyl group, a phenanthrolinyl group, a phenazinyl group,         a benzimidazolyl group, an isobenzothiazolyl group, a         benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group,         a tetrazolyl group, an imidazopyridinyl group, an         imidazopyrimidinyl group, an azacarbazolyl group,         —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),         —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and     -   Q₃₁ to Q₃₃ may respectively be defined the same as described         above.

In one exemplary embodiment, in Formulae 301, 301-1, and 301-2, R₃₀₁ to R₃₀₄ may each independently be selected from:

-   -   a phenyl group, a biphenyl group, a terphenyl group, a naphthyl         group, a fluorenyl group, a spiro-bifluorenyl group, a         benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl         group, an anthracenyl group, a fluoranthenyl group, a         triphenylenyl group, a pyrenyl group, a chrysenyl group, a         perylenyl group, a pentaphenyl group, a hexacenyl group, a         pentacenyl group, a thiophenyl group, a furanyl group, a         carbazolyl group, an indolyl group, an isoindolyl group, a         benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl         group, a dibenzothiophenyl group, a benzocarbazolyl group, a         dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl         group, an imidazolyl group, a pyrazolyl group, a thiazolyl         group, an isothiazolyl group, an oxazolyl group, an isoxazolyl         group, a thiadiazolyl group, an oxadiazolyl group, a pyrazinyl         group, a pyrimidinyl group, a pyridazinyl group, a triazinyl         group, a quinolinyl group, an isoquinolinyl group, a         benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl         group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl         group, a phenanthridinyl group, an acridinyl group, a         phenanthrolinyl group, a phenazinyl group, a benzimidazolyl         group, an isobenzothiazolyl group, a benzoxazolyl group, an         isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an         imidazopyridinyl group, an imidazopyrimidinyl group, and an         azacarbazolyl group; and     -   a phenyl group, a biphenyl group, a terphenyl group, a naphthyl         group, a fluorenyl group, a spiro-bifluorenyl group, a         benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl         group, an anthracenyl group, a fluoranthenyl group, a         triphenylenyl group, a pyrenyl group, a chrysenyl group, a         perylenyl group, a pentaphenyl group, a hexacenyl group, a         pentacenyl group, a thiophenyl group, a furanyl group, a         carbazolyl group, an indolyl group, an isoindolyl group, a         benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl         group, a dibenzothiophenyl group, a benzocarbazolyl group, a         dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl         group, an imidazolyl group, a pyrazolyl group, a thiazolyl         group, an isothiazolyl group, an oxazolyl group, an isoxazolyl         group, a thiadiazolyl group, an oxadiazolyl group, a pyrazinyl         group, a pyrimidinyl group, a pyridazinyl group, a triazinyl         group, a quinolinyl group, an isoquinolinyl group, a         benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl         group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl         group, a phenanthridinyl group, an acridinyl group, a         phenanthrolinyl group, a phenazinyl group, a benzimidazolyl         group, an isobenzothiazolyl group, a benzoxazolyl group, an         isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an         imidazopyridinyl group, an imidazopyrimidinyl group, and an         azacarbazolyl group, each substituted with at least one         substituent selected from deuterium, —F, —Cl, —Br, —I, a         hydroxyl group, a cyano group, a nitro group, an amidino group,         a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a         C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a         terphenyl group, a naphthyl group, a fluorenyl group, a         spiro-bifluorenyl group, a benzofluorenyl group, a         dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl         group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl         group, a chrysenyl group, a perylenyl group, a pentaphenyl         group, a hexacenyl group, a pentacenyl group, a thiophenyl         group, a furanyl group, a carbazolyl group, an indolyl group, an         isoindolyl group, a benzofuranyl group, a benzothiophenyl group,         a dibenzofuranyl group, a dibenzothiophenyl group, a         benzocarbazolyl group, a dibenzocarbazolyl group, a         dibenzosilolyl group, a pyridinyl group, an imidazolyl group, a         pyrazolyl group, a thiazolyl group, an isothiazolyl group, an         oxazolyl group, an isoxazolyl group, a thiadiazolyl group, an         oxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a         pyridazinyl group, a triazinyl group, a quinolinyl group, an         isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl         group, a naphthyridinyl group, a quinoxalinyl group, a         quinazolinyl group, a cinnolinyl group, a phenanthridinyl group,         an acridinyl group, a phenanthrolinyl group, a phenazinyl group,         a benzimidazolyl group, an isobenzothiazolyl group, a         benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group,         a tetrazolyl group, an imidazopyridinyl group, an         imidazopyrimidinyl group, an azacarbazolyl group,         —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),         —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and     -   Q₃₁ to Q₃₃ may respectively be the same as described above.

In one exemplary embodiment, the host may include an alkaline earth metal complex. For example, the host may be selected from a Be complex (for example, Compound H55), a Mg complex, and a Zn complex.

The host may include at least one selected from 9,10-di(2-naphthyl)anthracene (ADN), 2-methyl-9,10-bis(naphthalen-2-yl)anthracene (MADN), 9,10-di-(2-naphthyl)-2-t-butyl-anthracene (TBADN), 4,4′-bis(N-carbazolyl)-1,1′-biphenyl (CBP), 1,3-di-9-carbazolylbenzene (mCP), 1,3,5-tri(carbazol-9-yl)benzene (TCP), and Compounds H1 to H55, but exemplary embodiments are not limited thereto:

<Phosphorescent Dopant in the Emission Layer of the Organic Layer 150>

The phosphorescent dopant may include an organometallic complex represented by Formula 401 and Formula 402:

In Formulae 401 and 402,

-   -   M may be selected from iridium (Ir), platinum (Pt), palladium         (Pd), osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf),         europium (Eu), terbium (Tb), rhodium (Rh), and thulium (Tm),     -   L₄₀₁ may be selected from a ligand represented by Formula 402,         and xc1 may be 1, 2, or 3. When xc1 is two or more, two or more         of L₄₀₁(s) may be identical to or different from each other,     -   L₄₀₂ may be an organic ligand, and xc2 may be an integer of 0         to 4. When xc2 is two or more, two or more of L₄₀₂(s) may be         identical to or different from each other,     -   X₄₀₁ to X₄₀₄ may each independently be nitrogen or carbon,     -   X₄₀₁ and X₄₀₃ may be linked each other via a single bond or a         double bond, and X₄₀₂ and X₄₀₄ may be linked each other via a         single bond or a double bond,     -   A₄₀₁ and A₄₀₂ may each independently be a C₅-C₆₀ carbocyclic         group or a C₁-C₆₀ heterocyclic group,     -   X₄₀₅ may be a single bond, *—O—*′, *—S—*′, *—C(═O)—*′,         *—N(Q₄₁₁)-′, *—C(Q₄₁₁)(Q₄₁₂)-*′, *—C(Q₄₁₁)-C(Q₄₁₂)-*′,         *—C(Q₄₁₁)-*′, or *—C(Q₄₁₁)-*′, wherein Q₄₁₁ and Q₄₁₂ may be         hydrogen, deuterium, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy         group, a phenyl group, a biphenyl group, a terphenyl group, or a         naphthyl group,     -   X₄₀₆ may be a single bond, O or S,     -   R₄₀₁ and R₄₀₂ may each independently be selected from hydrogen,         deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a         nitro group, an amidino group, a hydrazino group, a hydrazono         group, a substituted or unsubstituted C₁-C₂₀ alkyl group, a         substituted or unsubstituted C₁-C₂₀ alkoxy group, a substituted         or unsubstituted C₃-C₁₀ cycloalkyl group, a substituted or         unsubstituted C₁-C₁₀ heterocycloalkyl group, a substituted or         unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or         unsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted or         unsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted         C₆-C₆₀ aryloxy group, a substituted or unsubstituted C₆-C₆₀         arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroaryl         group, a substituted or unsubstituted monovalent non-aromatic         condensed polycyclic group, a substituted or unsubstituted         monovalent non-aromatic condensed heteropolycyclic group,         —Si(Q401)(Q402)(Q403), —N(Q₄₀₁)(Q₄₀₂), —B(Q₄₀₁)(Q₄₀₂),         —C(═O)(Q₄₀₁), —S(═O)₂(Q₄₀₁), and —P(═O)(O₄₀₁)(Q₄₀₂),     -   Q₄₀₁ to Q₄₀₃ may each independently be selected from a C₁-C₁₀         alkyl group, a C₁-C₁₀ alkoxy group, a C₆-C₂₀ aryl group, and a         C₁-C₂₀ heteroaryl group,     -   xc11 and xc12 may each independently be an integer of 0 to 10,         and     -   in Formula 402, * and *′ each indicate a binding site to M of         Formula 401.

In one exemplary embodiment, in Formula 402, A₄₀₁ and A₄₀₂ may each independently be selected from a benzene group, a naphthalene group, a fluorene group, a spiro-bifluorene group, an indene group, a pyrrole group, a thiophene group, a furan group, an imidazole group, a pyrazole group, a thiazole group, an isothiazole group, an oxazole group, an isoxazole group, a pyridine group, a pyrazine group, a pyrimidine group, a pyridazine group, a quinoline group, an isoquinoline group, a benzoquinoline group, a quinoxaline group, a quinazoline group, a carbazole group, a benzimidazole group, a benzofuran group, a benzothiophene group, an isobenzothiophene group, a benzoxazole group, an isobenzoxazole group, a triazole group, a tetrazole group, an oxadiazole group, a triazine group, a dibenzofuran group, and a dibenzothiophene group.

In one or more exemplary embodiments, in Formula 402, i) X₄₀₁ may be nitrogen, and X₄₀₂ may be carbon, or ii) X₄₀₁ and X₄₀₂ may be both nitrogen.

In one or more exemplary embodiments, in Formula 402, R₄₀₁ and R₄₀₂ may each independently be selected from:

-   -   hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano         group, a nitro group, an amidino group, a hydrazino group, a         hydrazono group, a C₁-C₂₀ alkyl group, and a C₁-C₂₀ alkoxy         group;     -   a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted         with at least one substituent selected from deuterium, —F, —Cl,         —Br, —I, a hydroxyl group, a cyano group, a nitro group, an         amidino group, a hydrazino group, a hydrazono group, a phenyl         group, a naphthyl group, a cyclopentyl group, a cyclohexyl         group, an adamantanyl group, a norbornanyl group, and a         norbornenyl group;     -   a cyclopentyl group, a cyclohexyl group, an adamantanyl group, a         norbornanyl group, a norbornenyl group, a phenyl group, a         biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl         group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl         group, a pyridazinyl group, a triazinyl group, a quinolinyl         group, an isoquinolinyl group, a quinoxalinyl group, a         quinazolinyl group, a carbazolyl group, a dibenzofuranyl group,         and a dibenzothiophenyl group;     -   a cyclopentyl group, a cyclohexyl group, an adamantanyl group, a         norbornanyl group, a norbornenyl group a phenyl group, a         biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl         group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl         group, a pyridazinyl group, a triazinyl group, a quinolinyl         group, an isoquinolinyl group, a quinoxalinyl group, a         quinazolinyl group, a carbazolyl group, a dibenzofuranyl group,         and a dibenzothiophenyl group, each substituted with at least         one substituent selected from deuterium, —F, —Cl, —Br, —I, a         hydroxyl group, a cyano group, a nitro group, an amidino group,         a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a         C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexyl group, an         adamantanyl group, a norbornanyl group, a norbornenyl group, a         phenyl group, a biphenyl group, a terphenyl group, a naphthyl         group, a fluorenyl group, a pyridinyl group, a pyrazinyl group,         a pyrimidinyl group, a pyridazinyl group, a triazinyl group, a         quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,         a quinazolinyl group, a carbazolyl group, a dibenzofuranyl         group, and a dibenzothiophenyl group; and     -   —Si(Q₄₀₁)(Q₄₀₂)(Q₄₀₃), —N(Q₄₀₁)(Q₄₀₂), —B(Q₄₀₁)(Q₄₀₂),         —C(═O)(Q₄₀₁), —S(═O)₂(Q₄₀₁), and —P(═O)(O₄₀₁)(Q₄₀₂), and     -   Q₄₀₁ to Q₄₀₃ may each independently be selected from a C₁-C₁₀         alkyl group, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl         group, and a naphthyl group, but exemplary embodiments are not         limited thereto.

In one or more exemplary embodiments, in Formula 401, when xc1 is two or more, two A₄₀₁(s) among a plurality of L₄₀₁(s) may optionally be linked via a linking group, X₄₀₇, or two A₄₀₂(s) may optionally be linked via a linking group, X₄₀₈ (see Compounds PD1 to PD4 and PD7). X₄₀₇ and X₄₀₈ may each independently be a single bond, *—O—*′, *—S—*′, *—C(═O)—*′, *—N(Q₄₁₃)-*′, *—C(Q₄₁₃)(Q₄₁₄)-′, or *—C(Q₄₁₃)-C(Q₄₁₄)-*′ (wherein Q₄₁₃ and Q₄₁₄ may each independently be hydrogen, deuterium, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, or a naphthyl group), but exemplary embodiments are not limited thereto.

L₄₀₂ in Formula 401 may be a monovalent, divalent, or trivalent organic ligand. For example, L₄₀₂ may be selected from halogen, diketone (for example, acetylacetonate), carboxylic acid (for example, picolinate), —C(═O), isonitrile, —CN, and phosphorus (for example, phosphine, or phosphite), but exemplary embodiments are not limited thereto.

In one or more exemplary embodiments, the phosphorescent dopant may be selected from, for example, Compounds PD1 to PD25, but exemplary embodiments are not limited thereto:

<Fluorescent Dopant in the Emission Layer>

The fluorescent dopant may include an arylamine compound or a styrylamine compound.

The fluorescent dopant may include a compound represented by Formula 501:

In Formula 501,

-   -   Ar₅₀₁ may be a substituted or unsubstituted C₅-C₆₀ carbocyclic         group or a substituted or unsubstituted C₁-C₆₀ heterocyclic         group,     -   L₅₀₁ to L₅₀₃ may each independently be selected from a         substituted or unsubstituted C₃-C₁₀ cycloalkylene group, a         substituted or unsubstituted C₁-C₁₀ heterocycloalkylene group, a         substituted or unsubstituted C₃-C₁₀ cycloalkenylene group, a         substituted or unsubstituted C₁-C₁₀ heterocycloalkenylene group,         a substituted or unsubstituted C₆-C₆₀ arylene group, a         substituted or unsubstituted C₁-C₆₀ heteroarylene group, a         substituted or unsubstituted divalent non-aromatic condensed         polycyclic group, and a substituted or unsubstituted divalent         non-aromatic condensed heteropolycyclic group,     -   xd1 to xd3 may each independently be an integer of 0 to 3,     -   R₅₀₁ and R₅₀₂ may each independently be selected from a         substituted or unsubstituted C₃-C₁₀ cycloalkyl group, a         substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, a         substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a         substituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, a         substituted or unsubstituted C₆-C₆₀ aryl group, a substituted or         unsubstituted C₆-C₆₀ aryloxy group, a substituted or         unsubstituted C₆-C₆₀ arylthio group, a substituted or         unsubstituted C₁-C₆₀ heteroaryl group, a substituted or         unsubstituted monovalent non-aromatic condensed polycyclic         group, and a substituted or unsubstituted monovalent         non-aromatic condensed heteropolycyclic group, and,     -   xd4 may be an integer of 1 to 6.

In one exemplary embodiment, Ar₅₀₁ in Formula 501 may be selected from:

-   -   a naphthalene group, a heptalene group, a fluorene group, a         spiro-bifluorene group, a benzofluorene group, a dibenzofluorene         group, a phenalene group, a phenanthrene group, an anthracene         group, a fluoranthene group, a triphenylene group, a pyrene         group, a chrysene group, a naphthacene group, a picene group, a         perylene group, a pentaphene group, an indenoanthracene group,         and an indenophenanthrene group; and     -   a naphthalene group, a heptalene group, a fluorene group, a         spiro-bifluorene group, a benzofluorene group, a dibenzofluorene         group, a phenalene group, a phenanthrene group, an anthracene         group, a fluoranthene group, a triphenylene group, a pyrene         group, a chrysene group, a naphthacene group, a picene group, a         perylene group, a pentaphene group, an indenoanthracene group,         and an indenophenanthrene group, each substituted with at least         one substituent selected from deuterium, —F, —Cl, —Br, —I, a         hydroxyl group, a cyano group, a nitro group, an amidino group,         a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a         C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a         terphenyl group, and a naphthyl group.

In one or more exemplary embodiments, L₅₀₁ to L₅₀₃ in Formula 501 may each independently be selected from:

-   -   a phenylene group, a naphthylene group, a fluorenylene group, a         spiro-bifluorenylene group, a benzofluorenylene group, a         dibenzofluorenylene group, a phenanthrenylene group, an         anthracenylene group, a fluoranthenylene group, a         triphenylenylene group, a pyrenylene group, a chrysenylene         group, a perylenylene group, a pentaphenylene group, a         hexacenylene group, a pentacenylene group, a thiophenylene         group, a furanylene group, a carbazolylene group, an indolylene         group, an isoindolylene group, a benzofuranylene group, a         benzothiophenylene group, a dibenzofuranylene group, a         dibenzothiophenylene group, a benzocarbazolylene group, a         dibenzocarbazolylene group, a dibenzosilolylene group, and a         pyridinylene group; and     -   a phenylene group, a naphthylene group, a fluorenylene group, a         spiro-bifluorenylene group, a benzofluorenylene group, a         dibenzofluorenylene group, a phenanthrenylene group, an         anthracenylene group, a fluoranthenylene group, a         triphenylenylene group, a pyrenylene group, a chrysenylene         group, a perylenylene group, a pentaphenylene group, a         hexacenylene group, a pentacenylene group, a thiophenylene         group, a furanylene group, a carbazolylene group, an indolylene         group, an isoindolylene group, a benzofuranylene group, a         benzothiophenylene group, a dibenzofuranylene group, a         dibenzothiophenylene group, a benzocarbazolylene group, a         dibenzocarbazolylene group, a dibenzosilolylene group, and a         pyridinylene group, each substituted with at least one         substituent selected from deuterium, —F, —Cl, —Br, —I, a         hydroxyl group, a cyano group, a nitro group, an amidino group,         a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a         C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a         terphenyl group, a naphthyl group, a fluorenyl group, a         spiro-bifluorenyl group, a benzofluorenyl group, a         dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl         group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl         group, a chrysenyl group, a perylenyl group, a pentaphenyl         group, a hexacenyl group, a pentacenyl group, a thiophenyl         group, a furanyl group, a carbazolyl group, an indolyl group, an         isoindolyl group, a benzofuranyl group, a benzothiophenyl group,         a dibenzofuranyl group, a dibenzothiophenyl group, a         benzocarbazolyl group, a dibenzocarbazolyl group, a         dibenzosilolyl group, and a pyridinyl group.

In one or more exemplary embodiments, in Formula 501, R₅₀₁ and R₅₀₂ may each independently be selected from:

-   -   a phenyl group, a biphenyl group, a terphenyl group, a naphthyl         group, a fluorenyl group, a spiro-bifluorenyl group, a         benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl         group, an anthracenyl group, a fluoranthenyl group, a         triphenylenyl group, a pyrenyl group, a chrysenyl group, a         perylenyl group, a pentaphenyl group, a hexacenyl group, a         pentacenyl group, a thiophenyl group, a furanyl group, a         carbazolyl group, an indolyl group, an isoindolyl group, a         benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl         group, a dibenzothiophenyl group, a benzocarbazolyl group, a         dibenzocarbazolyl group, a dibenzosilolyl group, and a pyridinyl         group; and     -   a phenyl group, a biphenyl group, a terphenyl group, a naphthyl         group, a fluorenyl group, a spiro-bifluorenyl group, a         benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl         group, an anthracenyl group, a fluoranthenyl group, a         triphenylenyl group, a pyrenyl group, a chrysenyl group, a         perylenyl group, a pentaphenyl group, a hexacenyl group, a         pentacenyl group, a thiophenyl group, a furanyl group, a         carbazolyl group, an indolyl group, an isoindolyl group, a         benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl         group, a dibenzothiophenyl group, a benzocarbazolyl group, a         dibenzocarbazolyl group, a dibenzosilolyl group, and a pyridinyl         group, each substituted with at least one substituent selected         from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano         group, a nitro group, an amidino group, a hydrazino group, a         hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a         phenyl group, a biphenyl group, a terphenyl group, a naphthyl         group, a fluorenyl group, a spiro-bifluorenyl group, a         benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl         group, an anthracenyl group, a fluoranthenyl group, a         triphenylenyl group, a pyrenyl group, a chrysenyl group, a         perylenyl group, a pentaphenyl group, a hexacenyl group, a         pentacenyl group, a thiophenyl group, a furanyl group, a         carbazolyl group, an indolyl group, an isoindolyl group, a         benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl         group, a dibenzothiophenyl group, a benzocarbazolyl group, a         dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl         group and —Si(Q₃₁)(Q₃₂)(Q₃₃), and     -   Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀         alkyl group, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl         group, a terphenyl group, and a naphthyl group.

In one or more exemplary embodiments, xd4 in Formula 501 may be 2, but exemplary embodiments are not limited thereto.

For example, the fluorescent dopant may be selected from Compounds FD1 to FD22:

In one or more exemplary embodiments, the fluorescent dopant may be selected from the following compounds, but exemplary embodiments are not limited thereto:

<Electron Transport Region in the Organic Layer 150>

The electron transport region may have i) a single-layered structure including a single layer including a single material, ii) a single-layered structure including a single layer including a plurality of different materials, or iii) a multi-layered structure having a plurality of layers including a plurality of different materials.

The electron transport region may include at least one selected from a buffer layer, a hole blocking layer, an electron control layer, an electron transport layer, and an electron injection layer, but exemplary embodiments are not limited thereto.

For example, the electron transport region may have an electron transport layer/electron injection layer structure, a hole blocking layer/electron transport layer/electron injection layer structure, an electron control layer/electron transport layer/electron injection layer structure, or a buffer layer/electron transport layer/electron injection layer structure, wherein for each structure, constituting layers are sequentially stacked from an emission layer. However, exemplary embodiments of the structure of the electron transport region are not limited thereto.

The electron transport region (for example, a buffer layer, a hole blocking layer, an electron control layer, or an electron transport layer in the electron transport region) may include a metal-free compound including at least one π electron-depleted nitrogen-containing ring.

The “π electron-depleted nitrogen-containing ring” indicates a C₁-C₆₀ heterocyclic group having at least one *—N═*′ moiety as a ring-forming moiety.

For example, the “π electron-depleted nitrogen-containing ring” may be i) a 5-membered to 7-membered heteromonocyclic group having at least one *—N═*′ moiety, ii) a heteropolycyclic group in which two or more 5-membered to 7-membered heteromonocyclic groups each having at least one *—N═*′ moiety are condensed with each other, or iii) a heteropolycyclic group in which at least one of 5-membered to 7-membered heteromonocyclic groups, each having at least one *—N═*′ moiety, is condensed with at least one C5-C60 carbocyclic group.

Examples of the π electron-depleted nitrogen-containing ring include an imidazole, a pyrazole, a thiazole, an isothiazole, an oxazole, an isoxazole, a pyridine, a pyrazine, a pyrimidine, a pyridazine, an indazole, a purine, a quinoline, an isoquinoline, a benzoquinoline, a phthalazine, a naphthyridine, a quinoxaline, a quinazoline, a cinnoline, a phenanthridine, an acridine, a phenanthroline, a phenazine, a benzimidazole, an isobenzothiazole, a benzoxazole, an isobenzoxazole, a triazole, a tetrazole, an oxadiazole, a triazine, thiadiazol, an imidazopyridine, an imidazopyrimidine, and an azacarbazole, but are not limited thereto.

For example, the electron transport region may include a compound represented by Formula 601:

[Ar_(6o1)]_(xe11)-[(L₆₀₁)_(xe1)-R₆₀₁]_(xe21)  <Formula 601>

In Formula 601,

-   -   Ar₆₀₁ may be a substituted or unsubstituted C₅-C₆₀ carbocyclic         group or a substituted or unsubstituted C₁-C₆₀ heterocyclic         group,     -   xe11 may be 1, 2, or 3,     -   L₆₀₁ may be selected from a substituted or unsubstituted C₃-C₁₀         cycloalkylene group, a substituted or unsubstituted C₁-C₁₀         heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀         cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀         heterocycloalkenylene group, a substituted or unsubstituted         C₆-C₆₀ arylene group, a substituted or unsubstituted C₁-C₆₀         heteroarylene group, a substituted or unsubstituted divalent         non-aromatic condensed polycyclic group, and a substituted or         unsubstituted divalent non-aromatic condensed heteropolycyclic         group;     -   xe1 may be an integer of 0 to 5,     -   R₆₀₁ may be selected from a substituted or unsubstituted C₃-C₁₀         cycloalkyl group, a substituted or unsubstituted C₁-C₁₀         heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀         cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀         heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀         aryl group, a substituted or unsubstituted C₆-C₆₀ aryloxy group,         a substituted or unsubstituted C₆-C₆₀ arylthio group, a         substituted or unsubstituted C₁-C₆₀ heteroaryl group, a         substituted or unsubstituted monovalent non-aromatic condensed         polycyclic group, a substituted or unsubstituted monovalent         non-aromatic condensed heteropolycyclic group,         —Si(Q₆₀₁)(Q₆₀₂)(Q₆₀₃), —C(═O)(Q₆₀₁), —S(═O)₂(Q₆₀₁), and         —P(═O)(Q₆₀₁)(Q₆₀₂),     -   Q₆₀₁ to Q₆₀₃ may each independently be a C₁-C₁₀ alkyl group, a         C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, a         terphenyl group, or a naphthyl group, and     -   xe21 may be an integer of 1 to 5.

In one exemplary embodiment, at least one of Ar₆₀₁(s) in the number of xe11 and R₆₀₁(s) in the number of xe21 may include the π electron-depleted nitrogen-containing ring.

In one exemplary embodiment, ring Ar₆₀₁ in Formula 601 may be selected from:

-   -   a benzene group, a naphthalene group, a fluorene group, a         spiro-bifluorene group, a benzofluorene group, a dibenzofluorene         group, a phenalene group, a phenanthrene group, an anthracene         group, a fluoranthene group, a triphenylene group, a pyrene         group, a chrysene group, a naphthacene group, a picene group, a         perylene group, a pentaphene group, an indenoanthracene group, a         dibenzofuran group, a dibenzothiophene group, a carbazole group,         an imidazole group, a pyrazole group, a thiazole group, an         isothiazole group, an oxazole group, an isoxazole group, a         pyridine group, a pyrazine group, a pyrimidine group, a         pyridazine group, an indazole group, a purine group, a quinoline         group, an isoquinoline group, a benzoquinoline group, a         phthalazine group, a naphthyridine group, a quinoxaline group, a         quinazoline group, a cinnoline group, a phenanthridine group, an         acridine group, a phenanthroline group, a phenazine group, a         benzimidazole group, an isobenzothiazole group, a benzoxazole         group, an isobenzoxazole group, a triazole group, a tetrazole         group, an oxadiazole group, a triazine group, a thiadiazole         group, an imidazopyridine group, an imidazopyrimidine group, and         an azacarbazole group; and     -   a benzene group, a naphthalene group, a fluorene group, a         spiro-bifluorene group, a benzofluorene group, a dibenzofluorene         group, a phenalene group, a phenanthrene group, an anthracene         group, a fluoranthene group, a triphenylene group, a pyrene         group, a chrysene group, a naphthacene group, a picene group, a         perylene group, a pentaphene group, an indenoanthracene group, a         dibenzofuran group, a dibenzothiophene group, a carbazole group,         an imidazole group, a pyrazole group, a thiazole group, an         isothiazole group, an oxazole group, an isoxazole group, a         pyridine group, a pyrazine group, a pyrimidine group, a         pyridazine group, an indazole group, a purine group, a quinoline         group, an isoquinoline group, a benzoquinoline group, a         phthalazine group, a naphthyridine group, a quinoxaline group, a         quinazoline group, a cinnoline group, a phenanthridine group, an         acridine group, a phenanthroline group, a phenazine group, a         benzimidazole group, an isobenzothiazole group, a benzoxazole         group, an isobenzoxazole group, a triazole group, a tetrazole         group, an oxadiazole group, a triazine group, a thiadiazole         group, an imidazopyridine group, an imidazopyrimidine group, and         an azacarbazole group, each substituted with at least one         substituent selected from deuterium, —F, —Cl, —Br, —I, a         hydroxyl group, a cyano group, a nitro group, an amidino group,         a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a         C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a         terphenyl group, a naphthyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃),         —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and     -   Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀         alkyl group, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl         group, a terphenyl group, and a naphthyl group.

When xe11 in Formula 601 is two or more, two or more Ar₆₀₁(s) may be linked via a single bond.

In one or more exemplary embodiments, Ar₆₀₁ in Formula 601 may be an anthracene group.

In one or more exemplary embodiments, a compound represented by Formula 601 may be represented by Formula 601-1:

In Formula 601-1,

-   -   X₆₁₄ may be N or C(R₆₁₄), X₆₁₅ may be N or C(R₆₁₅), X₆₁₆ may be         N or C(R₆₁₆), and at least one selected from X₆₁₄ to X₆₁₆ may be         N,     -   L₆₁₁ to L₆₁₃ may each independently be the same as described in         connection with L₆₀₁,     -   xe611 to xe613 may each independently be the same as described         in connection with xe1,     -   R₆₁₁ to R₆₁₃ may each independently be the same as described in         connection with R₆₀₁, and     -   R₆₁₄ to R₆₁₆ may each independently be selected from hydrogen,         deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a         nitro group, an amidino group, a hydrazino group, a hydrazono         group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl         group, a biphenyl group, a terphenyl group, and a naphthyl         group.

In one exemplary embodiment, L₆₀₁ and L₆₁₁ to L₆₁₃ in Formulae 601 and 601-1 may each independently be selected from:

-   -   a phenylene group, a naphthylene group, a fluorenylene group, a         spiro-bifluorenylene group, a benzofluorenylene group, a         dibenzofluorenylene group, a phenanthrenylene group, an         anthracenylene group, a fluoranthenylene group, a         triphenylenylene group, a pyrenylene group, a chrysenylene         group, a perylenylene group, a pentaphenylene group, a         hexacenylene group, a pentacenylene group, a thiophenylene         group, a furanylene group, a carbazolylene group, an indolylene         group, an isoindolylene group, a benzofuranylene group, a         benzothiophenylene group, a dibenzofuranylene group, a         dibenzothiophenylene group, a benzocarbazolylene group, a         dibenzocarbazolylene group, a dibenzosilolylene group, a         pyridinylene group, an imidazolylene group, a pyrazolylene         group, a thiazolylene group, an isothiazolylene group, an         oxazolylene group, an isoxazolylene group, a thiadiazolylene         group, an oxadiazolylene group, a pyrazinylene group, a         pyrimidinylene group, a pyridazinylene group, a triazinylene         group, a quinolinylene group, an isoquinolinylene group, a         benzoquinolinylene group, a phthalazinylene group, a         naphthyridinylene group, a quinoxalinylene group, a         quinazolinylene group, a cinnolinylene group, a         phenanthridinylene group, an acridinylene group, a         phenanthrolinylene group, a phenazinylene group, a         benzimidazolylene group, an isobenzothiazolylene group, a         benzoxazolylene group, an isobenzoxazolylene group, a         triazolylene group, a tetrazolylene group, an         imidazopyridinylene group, an imidazopyrimidinylene group, and         an azacarbazolylene group; and     -   a phenylene group, a naphthylene group, a fluorenylene group, a         spiro-bifluorenylene group, a benzofluorenylene group, a         dibenzofluorenylene group, a phenanthrenylene group, an         anthracenylene group, a fluoranthenylene group, a         triphenylenylene group, a pyrenylene group, a chrysenylene         group, a perylenylene group, a pentaphenylene group, a         hexacenylene group, a pentacenylene group, a thiophenylene         group, a furanylene group, a carbazolylene group, an indolylene         group, an isoindolylene group, a benzofuranylene group, a         benzothiophenylene group, a dibenzofuranylene group, a         dibenzothiophenylene group, a benzocarbazolylene group, a         dibenzocarbazolylene group, a dibenzosilolylene group, a         pyridinylene group, an imidazolylene group, a pyrazolylene         group, a thiazolylene group, an isothiazolylene group, an         oxazolylene group, an isoxazolylene group, a thiadiazolylene         group, an oxadiazolylene group, a pyrazinylene group, a         pyrimidinylene group, a pyridazinylene group, a triazinylene         group, a quinolinylene group, an isoquinolinylene group, a         benzoquinolinylene group, a phthalazinylene group, a         naphthyridinylene group, a quinoxalinylene group, a         quinazolinylene group, a cinnolinylene group, a         phenanthridinylene group, an acridinylene group, a         phenanthrolinylene group, a phenazinylene group, a         benzimidazolylene group, an isobenzothiazolylene group, a         benzoxazolylene group, an isobenzoxazolylene group, a         triazolylene group, a tetrazolylene group, an         imidazopyridinylene group, an imidazopyrimidinylene group, and         an azacarbazolylene group, each substituted with at least one         substituent selected from deuterium, —F, —Cl, —Br, —I, a         hydroxyl group, a cyano group, a nitro group, an amidino group,         a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a         C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a         terphenyl group, a naphthyl group, a fluorenyl group, a         spiro-bifluorenyl group, a benzofluorenyl group, a         dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl         group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl         group, a chrysenyl group, a perylenyl group, a pentaphenyl         group, a hexacenyl group, a pentacenyl group, a thiophenyl         group, a furanyl group, a carbazolyl group, an indolyl group, an         isoindolyl group, a benzofuranyl group, a benzothiophenyl group,         a dibenzofuranyl group, a dibenzothiophenyl group, a         benzocarbazolyl group, a dibenzocarbazolyl group, a         dibenzosilolyl group, a pyridinyl group, an imidazolyl group, a         pyrazolyl group, a thiazolyl group, an isothiazolyl group, an         oxazolyl group, an isoxazolyl group, a thiadiazolyl group, an         oxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a         pyridazinyl group, a triazinyl group, a quinolinyl group, an         isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl         group, a naphthyridinyl group, a quinoxalinyl group, a         quinazolinyl group, a cinnolinyl group, a phenanthridinyl group,         an acridinyl group, a phenanthrolinyl group, a phenazinyl group,         a benzimidazolyl group, an isobenzothiazolyl group, a         benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group,         a tetrazolyl group, an imidazopyridinyl group, an         imidazopyrimidinyl group, and an azacarbazolyl group,     -   but exemplary embodiments are not limited thereto.

In one or more exemplary embodiments, xe1 and xe611 to xe613 in Formulae 601 and 601-1 may each independently be 0, 1, or 2.

In one or more exemplary embodiments, in Formulae 601 and 601-1, R₆₀₁ and R₆₁₁ to R₆₁₃ may each independently be selected from:

-   -   a phenyl group, a biphenyl group, a terphenyl group, a naphthyl         group, a fluorenyl group, a spiro-bifluorenyl group, a         benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl         group, an anthracenyl group, a fluoranthenyl group, a         triphenylenyl group, a pyrenyl group, a chrysenyl group, a         perylenyl group, a pentaphenyl group, a hexacenyl group, a         pentacenyl group, a thiophenyl group, a furanyl group, a         carbazolyl group, an indolyl group, an isoindolyl group, a         benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl         group, a dibenzothiophenyl group, a benzocarbazolyl group, a         dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl         group, an imidazolyl group, a pyrazolyl group, a thiazolyl         group, an isothiazolyl group, an oxazolyl group, an isoxazolyl         group, a thiadiazolyl group, an oxadiazolyl group, a pyrazinyl         group, a pyrimidinyl group, a pyridazinyl group, a triazinyl         group, a quinolinyl group, an isoquinolinyl group, a         benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl         group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl         group, a phenanthridinyl group, an acridinyl group, a         phenanthrolinyl group, a phenazinyl group, a benzimidazolyl         group, an isobenzothiazolyl group, a benzoxazolyl group, an         isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an         imidazopyridinyl group, an imidazopyrimidinyl group, and an         azacarbazolyl group;     -   a phenyl group, a biphenyl group, a terphenyl group, a naphthyl         group, a fluorenyl group, a spiro-bifluorenyl group, a         benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl         group, an anthracenyl group, a fluoranthenyl group, a         triphenylenyl group, a pyrenyl group, a chrysenyl group, a         perylenyl group, a pentaphenyl group, a hexacenyl group, a         pentacenyl group, a thiophenyl group, a furanyl group, a         carbazolyl group, an indolyl group, an isoindolyl group, a         benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl         group, a dibenzothiophenyl group, a benzocarbazolyl group, a         dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl         group, an imidazolyl group, a pyrazolyl group, a thiazolyl         group, an isothiazolyl group, an oxazolyl group, an isoxazolyl         group, a thiadiazolyl group, an oxadiazolyl group, a pyrazinyl         group, a pyrimidinyl group, a pyridazinyl group, a triazinyl         group, a quinolinyl group, an isoquinolinyl group, a         benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl         group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl         group, a phenanthridinyl group, an acridinyl group, a         phenanthrolinyl group, a phenazinyl group, a benzimidazolyl         group, an isobenzothiazolyl group, a benzoxazolyl group, an         isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an         imidazopyridinyl group, an imidazopyrimidinyl group, and an         azacarbazolyl group, each substituted with at least one         substituent selected from deuterium, —F, —Cl, —Br, —I, a         hydroxyl group, a cyano group, a nitro group, an amidino group,         a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a         C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a         terphenyl group, a naphthyl group, a fluorenyl group, a         spiro-bifluorenyl group, a benzofluorenyl group, a         dibenzofluorenyl group, a phenanthrenyl group, an anthracenyl         group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl         group, a chrysenyl group, a perylenyl group, a pentaphenyl         group, a hexacenyl group, a pentacenyl group, a thiophenyl         group, a furanyl group, a carbazolyl group, an indolyl group, an         isoindolyl group, a benzofuranyl group, a benzothiophenyl group,         a dibenzofuranyl group, a dibenzothiophenyl group, a         benzocarbazolyl group, a dibenzocarbazolyl group, a         dibenzosilolyl group, a pyridinyl group, an imidazolyl group, a         pyrazolyl group, a thiazolyl group, an isothiazolyl group, an         oxazolyl group, an isoxazolyl group, a thiadiazolyl group, an         oxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a         pyridazinyl group, a triazinyl group, a quinolinyl group, an         isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl         group, a naphthyridinyl group, a quinoxalinyl group, a         quinazolinyl group, a cinnolinyl group, a phenanthridinyl group,         an acridinyl group, a phenanthrolinyl group, a phenazinyl group,         a benzimidazolyl group, an isobenzothiazolyl group, a         benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group,         a tetrazolyl group, an imidazopyridinyl group, an         imidazopyrimidinyl group, and an azacarbazolyl group; and     -   —S(═O)₂(Q₆₀₁) and —P(═O)(Q₆₀₁)(Q₆₀₂), and     -   Q₆₀₁ and Q₆₀₂ may respectively be the same as described above.

The electron transport region may include at least one compound selected from Compounds ET1 to ET36, but exemplary embodiments are not limited thereto:

In one or more exemplary embodiments, the electron transport region may include at least one compound selected from 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), 4,7-diphenyl-1,10-phenanthroline (Bphen), Alq₃, BAlq, 3-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-4-phenyl-4H-1,2,4-triazole (TAZ), and NTAZ:

Thicknesses of the buffer layer, the hole blocking layer, and the electron control layer may each be in a range of about 20 Å to about 1,000 Å, for example, about 30 Å to about 300 Å. When the thicknesses of the buffer layer, the hole blocking layer, and the electron control layer are within these ranges, the electron blocking layer may have excellent electron blocking characteristics or electron control characteristics without a substantial increase in driving voltage.

A thickness of the electron transport layer may be in a range of about 100 Å to about 1,000 Å, for example, about 150 Å to about 500 Å. When the thickness of the electron transport layer is within the range described above, the electron transport layer may have satisfactory electron transport characteristics without a substantial increase in driving voltage.

The electron transport region (for example, the electron transport layer in the electron transport region) may further include, in addition to the materials described above, a metal-containing material.

The metal-containing material may include at least one selected from alkali metal complex and alkaline earth-metal complex. The alkali metal complex may include a metal ion selected from a Li ion, a Na ion, a K ion, a Rb ion, and a Cs ion, and the alkaline earth-metal complex may include a metal ion selected from a Be ion, a Mg ion, a Ca ion, a Sr ion, and a Ba ion. A ligand coordinated with the metal ion of the alkali metal complex or the alkaline earth-metal complex may be selected from a hydroxy quinoline, a hydroxy isoquinoline, a hydroxy benzoquinoline, a hydroxy acridine, a hydroxy phenanthridine, a hydroxy phenyloxazole, a hydroxy phenylthiazole, a hydroxy diphenyloxadiazole, a hydroxy diphenylthiadiazole, a hydroxy phenylpyridine, a hydroxy phenylbenzimidazole, a hydroxy phenylbenzothiazole, a bipyridine, a phenanthroline, and a cyclopentadiene, but exemplary embodiments are not limited thereto.

For example, the metal-containing material may include a Li complex. The Li complex may include, for example, Compound ET-D1 (lithium quinolate, LiQ) or ET-D2:

The electron transport region may include an electron injection layer that facilitates injection of electrons from the second electrode 190. The electron injection layer may directly contact the second electrode 190.

The electron injection layer may have i) a single-layered structure including a single layer including a single material, ii) a single-layered structure including a single layer including a plurality of different materials, or iii) a multi-layered structure having a plurality of layers including a plurality of different materials.

The electron injection layer may include an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal compound, an alkaline earth-metal compound, a rare earth metal compound, an alkali metal complex, an alkaline earth-metal complex, a rare earth metal complex, or any combinations thereof.

The alkali metal may be selected from Li, Na, K, Rb, and Cs. In one exemplary embodiment, the alkali metal may be Li, Na, or Cs. In one or more exemplary embodiments, the alkali metal may be Li or Cs, but exemplary embodiments are not limited thereto.

The alkaline earth metal may be selected from Mg, Ca, Sr, and Ba.

The rare earth metal may be selected from Sc, Y, Ce, Tb, Yb, and Gd.

The alkali metal compound, the alkaline earth-metal compound, and the rare earth metal compound may be selected from oxides and halides (for example, fluorides, chlorides, bromides, or iodides) of the alkali metal, the alkaline earth-metal, and the rare earth metal.

The alkali metal compound may be selected from alkali metal oxides, such as Li₂O, Cs₂O, or K₂O, and alkali metal halides, such as LiF, NaF, CsF, KF, LiI, NaI, CsI, or KI. In one exemplary embodiment, the alkali metal compound may be selected from LiF, Li₂O, NaF, LiI, NaI, CsI, and KI, but exemplary embodiments are not limited thereto.

The alkaline earth-metal compound may be selected from alkaline earth-metal oxides, such as BaO, SrO, CaO, Ba_(x)Sr_(1-x)O (0<x<1), or Ba_(x)Ca_(1-x)O (0<x<1). In one exemplary embodiment, the alkaline earth-metal compound may be selected from BaO, SrO, and CaO, but exemplary embodiments are not limited thereto.

The rare earth metal compound may be selected from YbF₃, ScF₃, ScO₃, Y₂O₃, Ce₂O₃, GdF₃, and TbF₃. In one exemplary embodiment, the rare earth metal compound may be selected from YbF₃, ScF₃, TbF₃, YbI₃, ScI₃, and TbI₃, but exemplary embodiments are not limited thereto.

The alkali metal complex, the alkaline earth-metal complex, and the rare earth metal complex may include an ion of alkali metal, alkaline earth-metal, and rare earth metal as described above, and a ligand coordinated with a metal ion of the alkali metal complex, the alkaline earth-metal complex, or the rare earth metal complex may be selected from hydroxy quinoline, hydroxy isoquinoline, hydroxy benzoquinoline, hydroxy acridine, hydroxy phenanthridine, hydroxy phenyloxazole, hydroxy phenylthiazole, hydroxy diphenyloxadiazole, hydroxy diphenylthiadiazole, hydroxy phenylpyridine, hydroxy phenylbenzimidazole, hydroxy phenylbenzothiazole, bipyridine, phenanthroline, and cyclopentadiene, but exemplary embodiments are not limited thereto.

The electron injection layer may include an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal compound, an alkaline earth-metal compound, a rare earth metal compound, an alkali metal complex, an alkaline earth-metal complex, a rare earth metal complex, or any combinations thereof, as described above. In one or more exemplary embodiments, the electron injection layer may further include an organic material. When the electron injection layer further includes an organic material, an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal compound, an alkaline earth-metal compound, a rare earth metal compound, an alkali metal complex, an alkaline earth-metal complex, a rare earth metal complex, or any combinations thereof may be homogeneously or non-homogeneously dispersed in a matrix including the organic material.

A thickness of the electron injection layer may be in a range of about 1 Å to about 100 Å, for example, about 3 Å to about 90 Å. When the thickness of the electron injection layer is within the range described above, the electron injection layer may have satisfactory electron injection characteristics without a substantial increase in driving voltage.

<Second Electrode 190>

The second electrode 190 may be disposed on the organic layer 150 having such a structure. The second electrode 190 may be a cathode which is an electron injection electrode, and in this regard, a material for forming the second electrode 190 may be selected from metal, an alloy, an electrically conductive compound, and a combination thereof, which have a relatively low work function.

The second electrode 190 may include at least one selected from lithium (Li), silver (Ag), magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), ITO, and IZO, but exemplary embodiments are not limited thereto. The second electrode 190 may be a transmissive electrode, a semi-transmissive electrode, or a reflective electrode.

The second electrode 190 may have a single-layered structure, or a multi-layered structure including two or more layers.

<Description of FIGS. 2 to 4>

An organic light-emitting device 20 of FIG. 2 includes a first capping layer 210, a first electrode 110, an organic layer 150, and a second electrode 190 which are sequentially stacked in this stated order, an organic light-emitting device 30 of FIG. 3 includes a first electrode 110, an organic layer 150, a second electrode 190, and a second capping layer 220 which are sequentially stacked in this stated order, and an organic light-emitting device 40 of FIG. 4 includes a first capping layer 210, a first electrode 110, an organic layer 150, a second electrode 190, and a second capping layer 220.

Regarding FIGS. 2 to 4, the first electrode 110, the organic layer 150, and the second electrode 190 may be understood by referring to the description presented in connection with FIG. 1.

In the organic layer 150 of each of the organic light-emitting devices 20 and 40, light generated in an emission layer may pass through the first electrode 110, which is a semi-transmissive electrode or a transmissive electrode, and the first capping layer 210 toward the outside, and in the organic layer 150 of each of the organic light-emitting devices 30 and 40, light generated in an emission layer may pass through the second electrode 190, which is a semi-transmissive electrode or a transmissive electrode, and the second capping layer 220 toward the outside.

The first capping layer 210 and the second capping layer 220 may increase external luminescent efficiency according to the principle of constructive interference.

The first capping layer 210 and the second capping layer 220 may each independently be an organic capping layer including an organic material, an inorganic capping layer including an inorganic material, or a composite capping layer including an organic material and an inorganic material.

At least one selected from the first capping layer 210 and the second capping layer 220 may each independently include at least one material selected from carbocyclic compounds, heterocyclic compounds, amine-based compounds, porphyrine derivatives, phthalocyanine derivatives, a naphthalocyanine derivatives, alkali metal complexes, and alkaline earth-based complexes. The carbocyclic compound, the heterocyclic compound, and the amine-based compound may be optionally substituted with a substituent containing at least one element selected from O, N, S, Se, Si, F, Cl, Br, and I. In one exemplary embodiment, at least one selected from the first capping layer 210 and the second capping layer 220 may each independently include an amine-based compound.

In one exemplary embodiment, at least one selected from the first capping layer 210 and the second capping layer 220 may each independently include the compound represented by Formula 201 or the compound represented by Formula 202.

In one or more exemplary embodiments, at least one selected from the first capping layer 210 and the second capping layer 220 may each independently include a compound selected from Compounds HT28 to HT33 and Compounds CP1 to CP5, but exemplary embodiments are not limited thereto:

Hereinbefore, the organic light-emitting device according to an exemplary embodiment has been described in connection with FIGS. 1-4. However, exemplary embodiments are not limited thereto.

Layers constituting the hole transport region, an emission layer, and layers constituting the electron transport region may be formed in a certain region by using one or more suitable methods selected from vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB) deposition, ink-jet printing, laser-printing, and laser-induced thermal imaging.

When layers constituting the hole transport region, an emission layer, and layers constituting the electron transport region are formed by vacuum deposition, the deposition may be performed at a deposition temperature of about 100° C. to about 500° C., a vacuum degree of about 10⁻⁸ torr to about 10⁻³ torr, and a deposition speed of about 0.01 Å/sec to about 100 Å/sec by taking into account a material to be included in a layer to be formed, and the structure of a layer to be formed.

When layers constituting the hole transport region, an emission layer, and layers constituting the electron transport region are formed by spin coating, the spin coating may be performed at a coating speed of about 2,000 rpm to about 5,000 rpm and at a heat treatment temperature of about 80° C. to about 200° C. by taking into account a material to be included in a layer to be formed, and the structure of a layer to be formed.

<General Definition of Substituents>

The term “C₁-C₆₀ alkyl group” as used herein refers to a linear or branched aliphatic saturated hydrocarbon monovalent group having 1 to 60 carbon atoms, and examples thereof include a methyl group, an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, an isoamyl group, and a hexyl group. The term “C₁-C₆₀ alkylene group” as used herein refers to a divalent group having the same structure as the C₁-C₆₀ alkyl group.

The term “C₂-C₆₀ alkenyl group” as used herein refers to a hydrocarbon group having at least one carbon-carbon double bond in the middle or at the terminus of the C₂-C₆₀ alkyl group, and examples thereof include an ethenyl group, a propenyl group, and a butenyl group. The term “C₂-C₆₀ alkenylene group” as used herein refers to a divalent group having the same structure as the C₂-C₆₀ alkenyl group.

The term “C₂-C₆₀ alkynyl group” as used herein refers to a hydrocarbon group having at least one carbon-carbon triple bond in the middle or at the terminus of the C₂-C₆₀ alkyl group, and examples thereof include an ethynyl group, and a propynyl group. The term “C₂-C₆₀ alkynylene group” as used herein refers to a divalent group having the same structure as the C₂-C₆₀ alkynyl group.

The term “C₁-C₆₀ alkoxy group” as used herein refers to a monovalent group represented by —OA₁₀₁ (wherein A₁₀₁ is the C₁-C₆₀ alkyl group), and examples thereof include a methoxy group, an ethoxy group, and an isopropyloxy group.

The term “C₃-C₁₀ cycloalkyl group” as used herein refers to a monovalent saturated hydrocarbon monocyclic group having 3 to 10 carbon atoms, and examples thereof include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group. The term “C₃-C₁₀ cycloalkylene group” as used herein refers to a divalent group having the same structure as the C₃-C₁₀ cycloalkyl group.

The term “C₁-C₁₀ heterocycloalkyl group” as used herein refers to a monovalent monocyclic group having at least one heteroatom selected from N, O, Si, P, and S as a ring-forming atom and 1 to 10 carbon atoms, and examples thereof include a 1,2,3,4-oxatriazolidinyl group, a tetrahydrofuranyl group, and a tetrahydrothiophenyl group. The term “C₁-C₁₀ heterocycloalkylene group” as used herein refers to a divalent group having the same structure as the C₁-C₁₀ heterocycloalkyl group.

The term “C₃-C₁₀ cycloalkenyl group” as used herein refers to a monovalent monocyclic group that has 3 to 10 carbon atoms and at least one carbon-carbon double bond in the ring thereof and no aromaticity, and examples thereof include a cyclopentenyl group, a cyclohexenyl group, and a cycloheptenyl group. The term “C₃-C₁₀ cycloalkenylene group” as used herein refers to a divalent group having the same structure as the C₃-C₁₀ cycloalkenyl group.

The term “C₁-C₁₀ heterocycloalkenyl group” as used herein refers to a monovalent monocyclic group that has at least one heteroatom selected from N, O, Si, P, and S as a ring-forming atom, 1 to 10 carbon atoms, and at least one double bond in its ring. Non-limiting examples of the C₁-C₁₀ heterocycloalkenyl group include a 4,5-dihydro-1,2,3,4-oxatriazolyl group, a 2,3-dihydrofuranyl group, and a 2,3-dihydrothiophenyl group. The term “C₁-C₁₀ heterocycloalkenylene group” as used herein refers to a divalent group having the same structure as the C₁-C₁₀ heterocycloalkenyl group.

The term “C₆-C₆₀ aryl group” as used herein refers to a monovalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms, and a C₆-C₆₀ arylene group used herein refers to a divalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms. Non-limiting examples of the C₆-C₆₀ aryl group include a phenyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a pyrenyl group, and a chrysenyl group. When the C₆-C₆₀ aryl group and the C₆-C₆₀ arylene group each include two or more rings, the rings may be fused to each other.

The term “C₁-C₆₀ heteroaryl group” as used herein refers to a monovalent group having a carbocyclic aromatic system that has at least one heteroatom selected from N, O, Si, P, and S as a ring-forming atom, in addition to 1 to 60 carbon atoms. The term “C₁-C₆₀ heteroarylene group” as used herein refers to a divalent group having a carbocyclic aromatic system that has at least one heteroatom selected from N, O, Si, P, and S as a ring-forming atom, in addition to 1 to 60 carbon atoms. Non-limiting examples of the C₁-C₆₀ heteroaryl group include a pyridinyl group, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, and an isoquinolinyl group. When the C₁-C₆₀ heteroaryl group and the C₁-C₆₀ heteroarylene group each include two or more rings, the rings may be condensed with each other.

The term “C₆-C₆₀ aryloxy group” as used herein refers to —OA₁₀₂ (wherein A₁₀₂ is the C₆-C₆₀ aryl group), and a C₆-C₆₀ arylthio group used herein indicates —SA₁₀₃ (wherein A₁₀₃ is the C₆-C₆₀ aryl group).

The term “monovalent non-aromatic condensed polycyclic group” as used herein refers to a monovalent group (for example, having 8 to 60 carbon atoms) having two or more rings condensed with each other, only carbon atoms as ring-forming atoms, and no aromaticity in its entire molecular structure. A detailed example of the monovalent non-aromatic condensed polycyclic group is a fluorenyl group. The term “divalent non-aromatic condensed polycyclic group” as used herein refers to a divalent group having the same structure as the monovalent non-aromatic condensed polycyclic group.

The term “monovalent non-aromatic condensed heteropolycyclic group” as used herein refers to a monovalent group (for example, having 1 to 60 carbon atoms) having two or more rings condensed to each other, at least one heteroatom selected from N, O, Si, P, and S, other than carbon atoms, as a ring-forming atom, and no aromaticity in its entire molecular structure. An example of the monovalent non-aromatic condensed heteropolycyclic group is a carbazolyl group. The term “divalent non-aromatic condensed heteropolycyclic group” as used herein refers to a divalent group having the same structure as the monovalent non-aromatic condensed heteropolycyclic group.

The term “C₅-C₆₀ carbocyclic group” as used herein refers to a monocyclic or polycyclic group having 5 to 60 carbon atoms in which a ring-forming atom is a carbon atom only. The C₅-C₆₀ carbocyclic group may be an aromatic carbocyclic group or a non-aromatic carbocyclic group. The C₅-C₆₀ carbocyclic group may be a ring, such as benzene, a monovalent group, such as a phenyl group, or a divalent group, such as a phenylene group. In one or more exemplary embodiments, depending on the number of substituents connected to the C₅-C₆₀ carbocyclic group, the C₅-C₆₀ carbocyclic group may be a trivalent group or a quadrivalent group.

The term “C₁-C₆₀ heterocyclic group” as used herein refers to a group having the same structure as the C₁-C₆₀ carbocyclic group, except that as a ring-forming atom, at least one heteroatom selected from N, O, Si, P, and S is used in addition to carbon (the number of carbon atoms may be in a range of 1 to 60).

At least one substituent of the substituted C₅-C₆₀ carbocyclic group, the substituted C₁-C₆₀ heterocyclic group, the substituted C₃-C₁₀ cycloalkylene group, the substituted C₁-C₁₀ heterocycloalkylene group, the substituted C₃-C₁₀ cycloalkenylene group, the substituted C₁-C₁₀ heterocycloalkenylene group, the substituted C₆-C₆₀ arylene group, the substituted C₁-C₆₀ heteroarylene group, the substituted divalent non-aromatic condensed polycyclic group, the substituted divalent non-aromatic condensed heteropolycyclic group, the substituted C₁-C₆₀ alkyl group, the substituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynyl group, the substituted C₁-C₆₀ alkoxy group, the substituted C₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀ heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenyl group, the substituted C₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀ arylthio group, the substituted C₁-C₆₀ heteroaryl group, the substituted monovalent non-aromatic condensed polycyclic group, and the substituted monovalent non-aromatic condensed heteropolycyclic group may be selected from:

-   -   deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a         nitro group, an amidino group, a hydrazino group, a hydrazono         group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀         alkynyl group, and a C₁-C₆₀ alkoxy group;     -   a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl         group, and a C₁-C₆₀ alkoxy group, each substituted with at least         one substituent selected from deuterium, —F, —Cl, —Br, —I, a         hydroxyl group, a cyano group, a nitro group, an amidino group,         a hydrazino group, a hydrazono group, a C₃-C₁₀ cycloalkyl group,         a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a         C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀         aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl         group, a monovalent non-aromatic condensed polycyclic group, a         monovalent non-aromatic condensed heteropolycyclic group,         —Si(Q_(ii))(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂), —B(Q₁₁)(Q₁₂), —C(═O)(Q₁₁),         —S(═O)₂(Q₁₁), and —P(═O)(Q₁₁)(Q₁₂);     -   a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a         C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a         C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio         group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic         condensed polycyclic group, and a monovalent non-aromatic         condensed heteropolycyclic group;     -   a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a         C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a         C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio         group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic         condensed polycyclic group, and a monovalent non-aromatic         condensed heteropolycyclic group, each substituted with at least         one substituent selected from deuterium, —F, —Cl, —Br, —I, a         hydroxyl group, a cyano group, a nitro group, an amidino group,         a hydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a         C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy         group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl         group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl         group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀         arylthio group, a C₁-C₆₀ heteroaryl group, a monovalent         non-aromatic condensed polycyclic group, a monovalent         non-aromatic condensed heteropolycyclic group,         —Si(Q₂₁)(Q₂₂)(Q₂₃), —N(Q₂₁)(Q₂₂), —B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁),         —S(═O)₂(Q₂₁), and —P(═O)(Q₂₁)(Q₂₂); and

—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ may each independently be selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, a biphenyl group, and a terphenyl group.

The term “Ph” used herein refers to a phenyl group, the term “Me” used herein refers to a methyl group, the term “Et” used herein refers to an ethyl group, the term “ter-Bu” or “Bu^(t)” used herein refers to a tert-butyl group, and the term “OMe” used herein refers to a methoxy group.

The term “biphenyl group” as used herein refers to “a phenyl group substituted with a phenyl group.” In other words, the “biphenyl group” is a substituted phenyl group having a C₆-C₆₀ aryl group as a substituent.

The term “terphenyl group” as used herein refers to “a phenyl group substituted with a biphenyl group.” In other words, the “terphenyl group” is a phenyl group having, as a substituent, a C₆-C₆₀ aryl group substituted with a C₆-C₆₀ aryl group.

* and *′ used herein, unless defined otherwise, each refer to a binding site to a neighboring atom in a corresponding formula.

Hereinafter, a compound according to exemplary embodiments and an organic light-emitting device according to exemplary embodiments will be described in detail with reference to Synthesis Examples and Examples. The wording “B was used instead of A” used in describing Synthesis Examples refers to that an identical molar equivalent of B was used in place of A.

SYNTHESIS EXAMPLES Synthesis Example 1: Synthesis of Compound 2

Synthesis of Intermediate 1-1

50.2 g (30 mmol) of (2-nitrophenyl)boronic acid, 108.80 g (30 mmol) of 2,4-dibromo-1-iodobenzene, 13.9 g (1.2 mmol) of Pd(PPh₃)₄ (tetrakis(triphenylphosphine)palladium), and 4.14 g (30 mmol) of K₂CO₃ were dissolved in 1,200 ml of a mixed solution of toluene/H₂O (a volume ratio of 3/1) and stirred at a temperature of 90° C. for 16 hours. The reaction solution was cooled to room temperature, and 300 ml of water was added thereto. An organic layer was extracted therefrom three times by using 100 ml of dichloromethane. A collected organic layer was dried by using magnesium sulfate, and then, the residual obtained by evaporating a solvent therefrom was separation-purified by silica gel column chromatography to obtain 60 g (yield of 56%) of Intermediate 1-1. The obtained compound was identified by LC-MS (C₁₂H₇Br₂NO₂: M+ cal.: 618.27).

Synthesis of Intermediate 1-2

60 g (168 mmol) of Intermediate 1-1 and 132 g (504 mmol) of triphenylphosphine were dissolved in o-dichlorobenzene and refluxed for 24 hours. When the reaction was completed, the reaction solution was cooled to room temperature, and 300 ml of water was added thereto. An organic layer was extracted therefrom three times by using 100 ml of dichloromethane. A collected organic layer was dried by using magnesium sulfate, and then, the residual obtained by evaporating a solvent therefrom was separation-purified by silica gel column chromatography to obtain 38 g (yield of 69%) of Intermediate 1-2. The obtained compound was identified by LC-MS (C₁₂H₇Br₂N: M+ cal.: 322.89).

Synthesis of Intermediate 1-3

100 ml of acetone was added to 10 g (3.07 mmol) of Intermediate 1-2 and then stirred. Potassium hydroxide was added thereto and refluxed for 30 minutes. Then, bromomethane was slowly added thereto and refluxed for 2 hours. When the reaction was completed, the reaction solution was cooled to room temperature, and 50 ml of water was added thereto. An organic layer was extracted therefrom three times by using 50 ml of dichloromethane. A collected organic layer was dried by using magnesium sulfate, and then, a residual obtained by evaporating a solvent therefrom was separation-purified by silica gel column chromatography to obtain 8.9 g (yield of 85%) of Intermediate 1-3. The obtained compound was identified by LC-MS (C₁₃H₉Br₂N: M+ cal.: 336.91).

Synthesis of Compound 2

5 g (14.7 mmol) of Intermediate 1-3, 8.32 g (33.9 mmol) of N-phenyl-[1,1′-biphenyl]-4-amine, 4.05 g (4.4 mmol) of Pd₂dba₃ (tris(dibenzylideneacetone)dipalladium(0)), 1.49 g (7.37 mmol) of tri-t-buthylphosphine, and 4.25 g (44.2 mmol) of sodium tert-butoxide were dissolved in 100 ml of toluene and stirred at a temperature of 100° C. for 12 hours. The reaction solution was cooled to room temperature, and 100 ml of water was added thereto. An organic layer was extracted therefrom three times by using 100 ml of dichloromethane. A collected organic layer was dried by using magnesium sulfate, and then, the residual obtained by evaporating a solvent therefrom was separation-purified by silica gel column chromatography to obtain 7 g (yield of 71%) of Compound 2. The obtained compound was identified by MS/FAB and ¹H NMR (C₄₉H₃₇N₃: M+ cal.: 667.86, found: 667.30).

Synthesis Example 2: Synthesis of Compound 8

Synthesis of Intermediate 2-1

100 ml of acetone was added to 10 g (3.07 mmol) of Intermediate 1-2 and then stirred. Potassium hydroxide was added thereto and refluxed for 30 minutes. Then, bromoethane was slowly added thereto and refluxed for 2 hours. When the reaction was completed, the reaction solution was cooled to room temperature, and 50 ml of water was added thereto. An organic layer was extracted therefrom three times by using 50 ml of dichloromethane. A collected organic layer was dried by using magnesium sulfate, and then, the residual obtained by evaporating a solvent therefrom was separation-purified by silica gel column chromatography to obtain 9 g (yield of 82.8%) of Intermediate 2-1. The obtained compound was identified by LC-MS (C₁₄H₁₁Br₂N: M+ cal.: 350.93).

Synthesis of Compound 8

5 g (14.2 mmol) of Intermediate 2-1, 5.51 g (32.6 mmol) of diphenylamine, 3.89 g (4.25 mmol) of Pd₂dba₃ (tris(dibenzylideneacetone)dipalladium(0)), 1.43 g (7.08 mmol) of tri-t-buthylphosphine, and 4.08 g (42.5 mmol) of sodium tert-butoxide were dissolved in 100 ml of toluene and refluxed at a temperature of 100° C. for 12 hours. The reaction solution was cooled to room temperature, and 100 ml of water was added thereto. An organic layer was extracted therefrom by using 100 ml of dichloromethane. A collected organic layer was dried by using magnesium sulfate, and then, the residual obtained by evaporating a solvent therefrom was separation-purified by silica gel column chromatography to obtain 5 g (yield of 67%) of Compound 8. The obtained compound was identified by MS/FAB and ¹H NMR (C₃₈H₃₁N₃: M+ cal.: 529.69, found: 529.25).

EXAMPLES Example 1

An ITO glass substrate was cut to a size of 50 mm×50 mm×0.5 mm, sonicated with acetone, isopropyl alcohol, and pure water each for 5 minutes, and then cleaned by exposure to ultraviolet rays and ozone for 30 minutes. Then, the ITO glass substrate was provided to a vacuum deposition apparatus.

2-TNATA (60 nm)/Compound 2 (30 nm)/ADN (host) and 2 wt % of DPABVi (dopant) (30 nm)/Alq₃ (30 nm)/LiF (1 nm)/Al (300 nm) were sequentially stacked on the ITO glass substrate, thereby completing the manufacture of an organic light-emitting device.

Examples 2 to 10 and Comparative Examples 1 to 4

Organic light-emitting devices were manufactured in the same manner as in Example 1, except that Compounds shown in Table 1 were each used instead of Compound 2 in forming a hole transport layer.

Evaluation Example 1

The driving voltage at the current density of 50 mA/cm², luminance, efficiency, and half lifespan (T50) at the current density of 100 mA/cm² in the organic light-emitting devices manufactured according to Examples 1 to 10 and Comparative Examples 1 to 4 were used by using the following methods, and results thereof are shown in Table 1.

-   -   Luminance: Power was supplied using a current-voltage meter         (Keithley SMU 236) and the luminance was measured by using a         luminance meter PR650.     -   Efficiency: Power was supplied using a current-voltage meter         (Keithley SMU 236), and the efficiency was measured by using a         luminance meter PR650.

The lifespan T50 indicates an amount of time (hr) that lapsed when luminance was 50% of initial luminance (100%) (@ 100 mA/cm²).

TABLE 1 Driving Current Hole transport voltage density Luminance Efficiency Emission T50 material (V) (mA/cm²) (cd/m²) (cd/A) color (hr) Example 1 Compound 2 4.32 50 3670 7.34 Blue 362 Example 2 Compound 8 4.21 50 3715 7.43 Blue 353 Example 3 Compound 9 4.22 50 3665 7.33 Blue 372 Example 4 Compound 12 4.26 50 3730 7.46 Blue 374 Example 5 Compound 15 4.25 50 3630 7.26 Blue 384 Example 6 Compound 22 4.41 50 3725 7.45 Blue 343 Example 7 Compound 27 4.26 50 3630 7.26 Blue 366 Example 8 Compound 30 4.32 50 3670 7.34 Blue 378 Example 9 Compound 33 4.45 50 3440 6.88 Blue 325 Example 10 Compound 35 4.60 50 3490 6.98 Blue 330 Comparative NPB 7.01 50 2645 5.29 Blue 258 Example 1 Comparative Compound A 4.89 50 3240 6.48 Blue 270 Example 2 Comparative Compound B 4.76 50 3197 6.39 Blue 257 Example 3 Comparative Compound C 4.80 50 3320 6.64 Blue 287 Example 4

Referring to Table 1, it is confirmed that the organic light-emitting devices of Examples 1 to 10 have a low driving voltage, high luminance, high efficiency, and a long lifespan, as compared with those of the organic light-emitting devices of Comparative Examples 1 to 4.

Organic light-emitting devices including the diamine-based compound may have a low driving voltage, high efficiency, high luminance, and a long lifespan, thereby implementing high-quality organic light-emitting devices and organic light-emitting apparatuses.

Although certain exemplary embodiments and implementations have been described herein, other embodiments and modifications will be apparent from this description. Accordingly, the inventive concepts are not limited to such embodiments, but rather to the broader scope of the appended claims and various obvious modifications and equivalent arrangements as would be apparent to a person of ordinary skill in the art. 

What is claimed is:
 1. A diamine-based compound represented by Formula 1:

wherein, in Formula 1, ring A is a C₅-C₆₀ carbocyclic group or a C₂-C₆₀ heterocyclic group, L₁ to L₄ are each independently selected from a substituted or unsubstituted C₅-C₆₀ carbocyclic group and a substituted or unsubstituted C₂-C₆₀ heterocyclic group, a1 to a4 are each independently an integer of 0 to 5, when a1 is two or more, two or more L₁(s) are identical to or different from each other, when a2 is two or more, two or more L₂(s) are identical to or different from each other, when a3 is two or more, two or more L₃(s) are identical to or different from each other, and when a4 is two or more, two or more L₄(s) are identical to or different from each other, when a1 is 0, *-(L₁)_(a1)-*′ is a single bond, when a2 is 0, *-(L₂)_(a2)-*′ is a single bond, when a3 is 0, *-(L₃)_(a3)-*′ is a single bond, and when a4 is 0, *-(L₄)_(a4)-*′ is a single bond, Ar₁ to Ar₄ and R₁ to R₃ are each independently selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazino group, a hydrazono group, a substituted or unsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstituted C₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or unsubstituted C₂-C₁₀ heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstituted C₁-C₆₀ hetero aryloxy group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —Si(Q₁)(Q₂)(Q₃), —B(Q₁)(Q₂), —C(═O)(Q₁), —N(Q₁)(Q₂), —P(═O)(Q₁)(Q₂), —P(═S)(Q₁)(Q₂), —S(═O)(Q₁)(Q₂), and —S(═O)₂(Q₁)(Q₂), wherein R₃ is not a phenyl group substituted with two —N(Q₁)(Q₂)(s), b1 to b4 are each independently an integer of 1 to 5, when b1 is two or more, two or more Ar₁(s) are identical to or different from each other, when b2 is two or more, two or more Ar₂(s) are identical to or different from each other, when b3 is two or more, two or more Ar₃(s) are identical to or different from each other, and when b4 is two or more, two or more Ar₄(s) are identical to or different from each other, c1 is an integer of 0 to 10, and c2 is an integer of 0 to 2, when c1 is two or more, two or more R₁(s) are identical to or different from each other, and when c2 is two or more, two or more R₂(s) are identical to or different from each other, wherein the diamine-based compound represented by Formula 1 is not a compound represented by Formula 1B,

at least one substituent of the substituted C₅-C₆₀ carbocyclic group, the substituted C₂-C₆₀ heterocyclic group, the substituted C₁-C₆₀ alkyl group, the substituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynyl group, the substituted C₁-C₆₀ alkoxy group, the substituted C₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀ heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenyl group, the substituted C₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀ arylthio group, the substituted C₁-C₆₀ heteroaryl group, the substituted C₁-C₆₀ hetero aryloxy group, the substituted monovalent non-aromatic condensed polycyclic group, and the substituted monovalent non-aromatic so condensed heteropolycyclic group is selected from: deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group; a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group, each substituted with at least one substituent selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazino group, a hydrazono group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —Si(Q₁₁)(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂), —B(Q₁₁)(Q₁₂), —C(═O)(Q₁₁), —S(═O)₂(Q₁₁), and —P(═O)(Q₁₁)(Q₁₂), a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, a biphenyl group, and a terphenyl group; a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, a biphenyl group, and a terphenyl group, each substituted with at least one substituent selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, a biphenyl group, a terphenyl group, —Si(Q₂₁)(Q₂₂)(Q₂₃), —N(Q₂₁)(Q₂₂), —B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁), —S(═O)₂(Q₂₁), and —P(═O)(Q₂₁)(Q₂₂); and —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), Q₁ to Q₃, Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ are each independently selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryl group substituted with a C₁-C₆₀ alkyl group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, a biphenyl group, and a terphenyl group, and and *′ each indicate a binding site to a neighboring atom.
 2. The diamine-based compound of claim 1, wherein: ring A is selected from a benzene group, a naphthalene group, an anthracene group, a phenanthrene group, a triphenylene group, a pyrene group, a chrysene group, a cyclopentadiene group, a 1,2,3,4-tetrahydronaphthalene group, a thiophene group, a furan group, a pyrrole group, an indole group, an indene group, a benzosilole group, a benzothiophene group, a benzofuran group, a carbazole group, a fluorene group, a dibenzosilole group, a dibenzothiophene group, a dibenzofuran group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, a quinoline group, an isoquinoline group, a quinoxaline group, a quinazoline group, a phenanthroline group, a pyrazole group, an imidazole group, a triazole group, an oxazole group, an isoxazole group, a thiazole group, an isothiazole group, an oxadiazole group, a thiadiazole group, a benzopyrazole group, a benzimidazole group, a benzoxazole group, a benzothiazole group, a benzoxadiazole group, a benzothiadiazole group, a 5,6,7,8-tetrahydroisoquinoline group, and a 5,6,7,8-tetrahydroquinoline group.
 3. The diamine-based compound of claim 1, wherein: L₁ to L₄ are each independently selected from: a phenylene group, a pentalenylene group, an indenylene group, a naphthylene group, an azulenylene group, a heptalenylene group, an indacenylene group, an acenaphthylene group, a fluorenylene group, a spiro-fluorenylene group, a benzofluorenylene group, a dibenzofluorenylene group, phenalenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylene group, a naphthacenylene group, a picenylene group, a perylenylene group, a pentaphenylene group, a hexacenylene group, a pentacenylene group, a rubicenylene group, a coronenylene group, an ovalenylene group, a pyrrolylene group, a thiophenylene group, a furanylene group, an imidazolylene group, a pyrazolylene group, a thiazolylene group, an isothiazolylene group, an oxazolylene group, an isoxazolylene group, a pyridinylene group, a pyrazinylene group, a pyrimidinylene group, a pyridazinylene group, an isoindolylene group, an indolylene group, an indazolylene group, a purinylene group, a quinolinylene group, an isoquinolinylene group, a benzoquinolinylene group, a phthalazinylene group, a naphthyridinylene group, a quinoxalinylene group, a quinazolinylene group, a cinnolinylene group, a carbazolylene group, a phenanthridinylene group, an acridinylene group, a phenanthrolinylene group, a phenazinylene group, a benzoimidazolylene group, a benzofuranylene group, a benzothiophenylene group, an isobenzothiazolylene group, a benzoxazolylene group, an isobenzoxazolylene group, a triazolylene group, a tetrazolylene group, an oxadiazolylene group, a triazinylene group, a dibenzofuranylene group, adibenzothiophenylene group, a benzocarbazolylene group, and a dibenzocarbazolylene group; and a phenylene group, a pentalenylene group, an indenylene group, a naphthylene group, an azulenylene group, a heptalenylene group, an indacenylene group, an acenaphthylene group, a fluorenylene group, a spiro-fluorenylene group, a benzofluorenylene group, a dibenzofluorenylene group, a phenalenylene group, a phenanthrenylene group, an anthracenylene group, a fluoranthenylene group, a triphenylenylene group, a pyrenylene group, a chrysenylene group, a naphthacenylene group, a picenylene group, a perylenylene group, a pentaphenylene group, a hexacenylene group, a pentacenylene group, a rubicenylene group, a coronenylene group, an ovalenylene group, a pyrrolylene group, a thiophenylene group, a furanylene group, an imidazolylene group, a pyrazolylene group, a thiazolylene group, an isothiazolylene group, an oxazolylene group, an isoxazolylene group, a pyridinylene group, a pyrazinylene group, a pyrimidinylene group, a pyridazinylene group, an isoindolylene group, an indolylene group, an indazolylene group, a purinylene group, a quinolinylene group, an isoquinolinylene group, a benzoquinolinylene group, a phthalazinylene group, a naphthyridinylene group, a quinoxalinylene group, a quinazolinylene group, a cinnolinylene group, a carbazolylene group, a phenanthridinylene group, an acridinylene group, a phenanthrolinylene group, a phenazinylene group, a benzimidazolylene group, a benzofuranylene group, a benzothiophenylene group, an isobenzothiazolylene group, a benzoxazolylene group, an isobenzoxazolylene group, a triazolylene group, a tetrazolylene group, an oxadiazolylene group, a triazinylene group, a dibenzofuranylene group, a dibenzothiophenylene group, a benzocarbazolylene group, and a dibenzocarbazolylene group, each substituted with at least one substituent selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an azulenyl group, a heptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, a so dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group, a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, a thiadiazolyl group, and an imidazopyridinyl group.
 4. The diamine-based compound of claim 1, wherein: Ar₁ to Ar₄ and R₁ to R₃ are each independently selected from: hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a C₂-C₂₀ alkenyl group, a C₂-C₂₀ alkynyl group, and a C₁-C₂₀ alkoxy group; a C₁-C₂₀ alkyl group, a C₂-C₂₀ alkenyl group, a C₂-C₂₀ alkynyl group, and a C₁-C₂₀ alkoxy group, each substituted with at least one substituent selected from deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cycloctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a naphthyl group, a pyridinyl group, a pyrimidinyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cycloctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, and an imidazopyrimidinyl group; a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cycloctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, and an imidazopyrimidinyl group, each substituted with at least one substituent selected from deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a C₂-C₂₀ alkenyl group, a C₂-C₂₀ alkynyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cycloctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and —B(Q₁)(Q₂), —P(Q₁)(Q₂), and —C(═O)(Q₁), wherein R₃ is not a phenyl group substituted with two —N(Q₁)(Q₂)(s), and Q₁ to Q₃ and Q₃₁ to Q₃₃ are each as defined in claim
 1. 5. The diamine-based compound of claim 1, wherein: Ar₁ to Ar₄ are each independently selected from groups represented by Formulae 5-1 to 5-42:

wherein, in Formulae 5-1 to 5-42, Y₃₁ is 0, S, C(Z₃₅)(Z₃₆), N(Z₃₇), or Si(Z₃₈)(Z₃₉), Z₃₁ to Z₃₉ are each independently selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a spiro-fluorene-benzofluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a triazinyl group, a dibenzofuranyl group, and a dibenzothiophenyl group, e2 is an integer of 0 to 2, e3 is an integer of 0 to 3, e4 is an integer of 0 to 4, e5 is an integer of 0 to 5, e6 is an integer of 0 to 6, e7 is an integer of 0 to 7, e9 is an integer of 0 to 9, and * indicates a binding site to a neighboring atom.
 6. The diamine-based compound of claim 1, wherein: Ar₁ to Ar₄ are each independently selected from groups represented by Formulae 6-1 to 6-11:


7. The diamine-based compound of claim 1, wherein: R₁ and R₂ are each independently selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazino group, a hydrazono group, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a ter-butyl group, a pentyl group, an isoamyl group, a hexyl group, a phenyl group, and a biphenyl group.
 8. The diamine-based compound of claim 1, wherein: R₃ is selected from: hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazino group, a hydrazono group, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a ter-butyl group, pentyl group, an isoamyl group, and a hexyl group; and groups represented by Formulae 8-1 to 8-20:


9. The diamine-based compound of claim 1, wherein: R₃ is selected from: a methyl group and an ethyl group; and groups represented by Formulae 9-1 to 9-4:


10. The diamine-based compound of claim 1, wherein: b1 to b4 are each
 1. 11. The diamine-based compound of claim 1, wherein: the diamine-based compound is represented by Formula 1A:

wherein, in Formula 1A, L₁ to L₄, a1 to a4, Ar₁ to Ar₄, b1 to b4, and R₃ are respectively as defined in claim
 1. 12. The diamine-based compound of claim 1, wherein: the diamine-based compound is selected from Compounds 1 to 39:


13. An organic light-emitting device comprising: a first electrode; a second electrode facing the first electrode; and an organic layer between the first electrode and the second electrode, wherein the organic layer comprises an emission layer and at least one of the diamine-based compound of claim
 1. 14. The organic light-emitting device of claim 13, wherein the first electrode is an anode, the second electrode is a cathode, and the organic layer further comprises a hole transport region disposed between the first electrode and the emission layer and an electron transport region disposed between the emission layer and the second electrode, the hole transport region comprises at least one layer selected from the group consisting of a hole injection layer, a first hole transport layer, a second hole transport layer, an emission auxiliary layer, and an electron blocking layer, and the electron transport region comprises at least one layer selected from the group consisting of a hole blocking layer, an electron transport layer, and an electron injection layer.
 15. The organic light-emitting device of claim 14, wherein the hole transport region comprises the diamine-based compound.
 16. The organic light-emitting device of claim 14, wherein: the hole transport region comprises a first hole transport layer, and the first hole transport layer comprises the diamine-based compound.
 17. The organic light-emitting device of claim 14, wherein: the hole transport region comprises the hole injection layer, the first hole transport layer, and the second hole transport layer, the second hole transport layer comprises the first hole transport layer and the emission layer, the hole injection layer and the first hole transport layer comprise the diamine-based compound, and the diamine-based compound comprised in the hole injection layer and the diamine-based compound comprised in the first hole transport layer are identical to or different from each other.
 18. The organic light-emitting device of claim 17, wherein: the second hole transport layer further comprises the diamine-based compound, the diamine-based compound comprised in the hole injection layer and the diamine-based compound comprised in the second hole transport layer are identical to or different from each other, and the diamine-based compound comprised in the first hole transport layer and the diamine-based compound comprised in the second hole transport layer are identical to or different from each other.
 19. The organic light-emitting device of claim 14, wherein: the hole transport region further comprises a p-dopant, and the p-dopant has a lowest unoccupied molecular orbital (LUMO) level of −3.5 eV or less.
 20. The organic light-emitting device of claim 19, wherein the p-dopant comprises a quinone derivative. 